Let’s add boron powder

elements110005
‘Boron’ page from Theodore Gray’s book, The Elements

Boron is a metalloid: an intermediate between the metals and non-metals. It exists in many polymorphs (different crystal lattice structures), some of which exhibit more metallic character than others. Metallic boron is non-toxic, extremely hard and has a very high melting point: only 11 elements have a higher melting point than boron.

British scientist Sir Humphrey Davy described boron thus:

“[Boron is] of the darkest shades of olive. It is opake[sic], very friable, and its powder does not scratch glass. If heated in the atmosphere, it takes fire at a temperature below the boiling point of olive oil, and burns with a red light and with scintillations like charcoal” – Sir Humphrey Davy in 1809

Initial condition

Before we add the 1.00 mol of boron into our reaction vessel, we need to recall what’s already in there from our experiments so far:

  • H2(g): 0.70 mol
  • He(g): 1.00 mol
  • Li(s): 0.40 mol
  • LiH(s): 0.60 mol
  • Be(s): 1.00 mol

The temperature of our vessel is 99 °C and the pressure of the gaseous phase is 525.5 kPa.

Now, let’s add our 1.00 mol of boron powder.

Which reactions take place?

Boron reacts with hydrogen gas to produce a colourless gas called borane, BH3(g), according to the following equation[1]:

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Boron also reacts with lithium in very complex ways. If we heat the vessel up to 350 °C, we’d expect to see the formation of a boron-lithium system with chemical formula B3Li according to this equation[2]:

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Notice that now we’ve heated up our vessel to 350 °C to allow this reaction to happen, the lithium at the bottom of the vessel has melted.

Boron reacts with lithium hydride as well, but only at temperatures around 688 °C. With our vessel’s temperature set at 350 °C, we won’t observe this particular reaction in our experiment.[3]

Some allotropes of boron – in particular, the alpha allotrope that was discovered in 1958 – is capable of reacting with beryllium to form BeB12. Because we’re using beryllium powder, which has semi-random  symmetry, we won’t see any BeB12 forming in our vessel. Alpha-boron only exists at pressures higher than around 3500 kPa. At our moderate pressure of only 525.5 kPa, powdered (semi-random) boron will prevail and no BeB12 will form.[4]

For simplicity’s sake, let’s assume that the two reactions above take place with equal preference.

Boron powder reacts with hydrogen gas

Let’s do an ice table to find out how much borane we make.

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A quick n/ratio calculation shows us that the hydrogen gas is limiting in this reaction:

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We can expect all of the hydrogen gas to react with the boron powder.

units are mol 2 B 3 H2 2 BH3
I 0.50 0.70 0
C -0.466 -0.70 +0.466
E 0.0333 0 0.466

Borane is very unstable as BH3, and it would probably dimerise into B2H6(g). This is still a gas at 350 °C and is much more stable than BH3. For the rest of this experiment we’ll assume that our 0.466 mol of BH3 has dimerised completely into 0.233 mol of B2H6.

Boron powder reacts with lithium

With the molar ratios present in our vessel, at 350 °C, we’d expect to witness the formation of a boron-lithium system, with chemical formula B3Li.

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A quick n/ratio calculation shows that in this reaction, the boron powder is limiting.

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All of the remaining boron therefore reacts with lithium. To calculate exactly how much B3Li we’ve created, let’s do another ice table:

units are mol 3 B Li B3Li
I 0.533 0.40 0
C -0.533 -0.178 +0.178
E 0 0.222 0.178

What’s in our vessel after adding boron?

We have the following gas mixture in our vessel:

Helium gas, He(g): 1.00 mol

Helium is an inert noble gas that will probably remain in the vessel until the end of the experiment. It’s used in party balloons.

Borane gas, B2H6(g): 0.233 mol

We made this today. Borane is used in the synthesis of organic chemicals via a process called hydroboration. An example of hydroboration is shown below.

250px-hydroboration-oxidation_of_1-methyl-cyclohex-1-ene

At the bottom of the vessel, there’s a sludge, which contains the following liquids and solids:

Molten lithium, Li(l): 0.22 mol

Lithium is used in the production of ceramics, batteries, grease, pharmaceuticals and many other applications. We’ve got 0.22 moles of lithium, which is about 1.5 grams.

Beryllium powder, Be(s): 1.00 mol

Beryllium is used as an alloying agent in producing beryllium copper, which is used in springs, electrical contacts, spot-welding electrodes, and non-sparking tools.

Lithium hydride, LiH(s): 0.60 mol

Lithium hydride is used in shielding nuclear reactors and also has the potential to store hydrogen gas in vehicles. Lithium hydride is highly reactive with water.

Boron-lithium system, B3Li(s): 0.178 mol

We made this today… but what is it? Not much is known about this compound – in fact, it doesn’t even have a name other than “boron-lithium system, B3Li”. It’ll probably decompose eventually in our experiment – maybe when we alter the pressure or temperature of the vessel at some later stage. We’ll need to keep an eye on this one.

The original H2(g) and B(s) have been reacted completely in our experiment.

What’s the pressure in our vessel now?

At the end of our reaction, the temperature of our vessel is still set at 350 °C and the pressure of the gaseous phase inside the vessel can be calculated to be a moderate 638 kPa as follows:

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*It should also be noted that some evidence exists for a reaction between LiH and BH3, forming Li(BH4). The reaction seems to take place stepwise with increasing temperature. A quick read of this paper suggests that in our vessel, which is at 350 °C, any Li(BH4) formed would actually break back down into boron powder and hydrogen gas, which would in turn react with each other and with lithium metal to form BH3 and LiH again. The net result would be a negligible net gain of LiH and a negligible net loss of boron powder. We will continue calculating this Periodic Table Smoothie under the assumption that if any Li(BH4) forms, it breaks down before we add the next element, and the overall effect on our system is negligible.

**Li(BH4) is an interesting compound: it’s been touted as a potential means of storing hydrogen gas in vehicles – it’s safer and releases hydrogen more readily than LiH, which was mentioned above.[5]

Next week, we’ll add element number 6, carbon, and see what happens.

References

  1. “Borane”. Wikipedia. N.p., 2016. Web. 14 Apr. 2016.
  2. Okamoto, H. “The B-Li (Boron-Lithium) System”. Bulletin of Alloy Phase Diagrams 10.3 (1989): 230-232.
  3. Matkovich, V. I. Boron And Refractory Borides. Berlin: Springer-Verlag, 1977. Print.
  4. Gaulé, G. K. Boron, Volume 2: Preparation, Properties And Applications. New York: Plenum Press, 1965. Print.
  5. Saldan, Ivan. “A Prospect For Libh4 As On-Board Hydrogen Storage”. Open Chemistry 9.5 (2011): n. pag. Web.

Let’s add beryllium powder

elements110004
‘Beryllium’ page from Theodore Gray’s book, The Elements

Initial condition

  • H2(g): 0.70 mol
  • He(g): 1.00 mol
  • Li(s): 0.40 mol (still solid: it melts at 180.5 degrees)
  • LiH(s): 0.60 mol
  • Pressure = 525.5 kPa
  • Temperature = 99°C

No reactions!

Beryllium doesn’t react with any of the things in the vessel: H2(g), He(g), Li(s) or LiH(s). My one mole of beryllium powder (which would cost me over $70) would just sit at the bottom of the vessel doing nothing.

With not much else to write about in the Periodic Table Smoothie this week, it might be a good idea to calculate how much this Periodic Table Smoothie would have cost in real life.

Element Cost per kg[1]  Molar mass  Cost per mole
H2  $              4.00 2  $       0.008
He  $            52.00 4  $       0.21
Li  $          270.00 6.941  $       1.87
Be  $      7,840.00 9.01  $    70.64
B (next week)  $    11,140.00 10.811  $  120.43
TOTAL cost of 1.00 mol of each of the first five elements  $        193.16

Conclusion

The addition of beryllium was highly uneventful. The vessel still contains the following:

  • H2(g): 0.70 mol
  • He(g): 1.00 mol
  • Li(s): 0.40 mol (still solid: it melts at 180.5 degrees)
  • LiH(s): 0.60 mol
  • Pressure = 525.5 kPa
  • Temperature = 99°C

We’ll add boron next week and see what happens.

Let’s add lithium powder

Lithium: a page from Theodore Gray's book The Elements
Lithium: a page from Theodore Gray’s book The Elements

Initial condition

  • Hydrogen gas, H2(g): 1.00 mol
  • Helium gas, He(g): 1.00 mol

Last week, our vessel contained a mixture of hydrogen and helium gases. No chemical reactions have occurred so far, but that is about to change. Today, we’ll add 1.00 mole of lithium powder to the mixture and observe our first chemical reaction.

What does lithium look like?

Lithium is a soft, silvery metal with the consistency of Parmesan cheese. Lumps of lithium can be cut with a knife and it’s so light that it floats on oil. It would float on water as well if it weren’t for the violent reaction that would take place. Lithium is very well-known by science students for its ability to react with water, producing hydrogen gas and an alkaline solution of lithium hydroxide.

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There’s no water in our vessel so the above reaction won’t actually take place. We’ve only got hydrogen gas and helium gas inside. Let’s see if our powdered lithium reacts with either of those gases.

Will the lithium powder react in our vessel?

Yes! Lithium reacts with hydrogen gas very slowly. One paper by NASA cited a reaction occurring at 29°C but the yield and rate were both very low. Because I want to initiate as many reactions as possible in this experiment, I’m going to heat my vessel to 99°C by immersing it in a bath of hot water. According to the NASA paper, this temperature would give my reaction a 60% yield after two hours.

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Lithium hydride is beginning to collect in the bottom of my 10-litre vessel. It’s a grey-to-colourless solid with a high melting point.

How much of each substance do we now have in the vessel?

First, we need to know which reagent is limiting. We can calculate this by using the following rule:

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Let’s substitute the values into the expression for all the reactants in this reaction: Li(s) and H2(g).

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If the yield was 100% (i.e. a complete reaction), I’d expect to make 1.00 mole of lithium hydride. However, we’re only going to get 0.60 moles because according to the NASA paper, the yield of this reaction is only 60% at my chosen temperature.

Let’s do an ‘ice’ table to find out how much of each reactant reacts, and hence how much of each substance we have left in our reactor vessel.

units are mol 2Li H2 2LiH
I (initial) 1.00 1.00 0
C (change) -0.60 -0.30 +0.60
E (equilibrium) 0.40 0.70 0.60

By the end of our reaction, we’d have:

  • H2(g): 0.70 mol
  • He(g): 1.00 mol
  • Li(s): 0.40 mol (still solid: it melts at 180.5 degrees)
  • LiH(s): 0.60 mol

What does 0.60 mol LiH look like?

Let’s use the density formula to try find out how many spoonfuls of LiH we’ve created.

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We’ve made 6.11 millilitres of lithium hydride powder! That’s a heaped teaspoon of LiH.

What’s the resulting pressure in the vessel?

Our elevated temperature of 99°C will have caused a considerable pressure increase inside the vessel.

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That’s 5.2 atmospheres (atm) of pressure, which is quite high. A typical car tyre is about 2 atm for comparison.

What if the vessel exploded?

BANG. The contents of the vessel, after they’ve rained down on an unsuspecting crowd, would react explosively with the water and other compounds in our bodies to produce caustic lithium hydroxide and toxic lithium salts. I recommend stepping away from the vessel and behind a thick safety screen at this point. Even though our imaginary vessel is quite strong, we better put on a lab coat and safety glasses as well—just in case.

Conclusion after adding lithium powder

  • H2(g): 0.70 mol
  • He(g): 1.00 mol
  • Li(s): 0.40 mol (still solid: it melts at 180.5 degrees)
  • LiH(s): 0.60 mol
  • Pressure = 525.5 kPa
  • Temperature = 99°C

Next week, we’ll add 1.00 mole of beryllium to the vessel and see what happens.

Reference: Smith, R. L.; Miser, J. W. (1963). Compilation of the properties of lithium hydride. NASA

Let’s add helium gas

elements1100021
‘Helium’ page from Theodore Gray’s amazing book, The Elements

Last week, we put 1.00 mole of hydrogen gas into a cylinder. The resulting pressure was 243 kPa and the temperature was maintained steady at 20°C. This week, we’ll add 1.00 mol of helium gas, He(g), to the vessel and see what happens.

Will the helium react with the hydrogen?

No. Helium is completely inert. Hydrogen and helium will co-exist without undergoing any chemical reactions.

What will the resulting pressure be?

This is a very simple calculation. With 2.00 moles of gas in the vessel, the pressure would be double what it was before. This is known as Dalton’s law of partial pressures: the total pressure in a vessel is equal to the sum of all the pressure of the individual gases in the vessel.

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Let’s convert that into pounds per square inch (psi) for easy comparison with everyday objects.

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That’s about the same as a hard bicycle tyre.

How fast are the molecules moving?

Remember from last week that when our vessel contained only hydrogen gas, the molecules were moving around randomly with an average speed of 1760 metres per second.

Kinetic molecular theory states that the kinetic energy of a gas is directly proportional to the temperature of that gas. The formula for kinetic energy is shown below:

image127.png

At constant temperature, heavier particles move more slowly than lighter ones. Even though they have the same kinetic energy, helium atoms at 20 °C move slower than hydrogen molecules at 20 °C because they have almost exactly double the mass. How much slower does the helium move? Let’s find out.

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The molecules are moving at 1245 metres per second, or 4482 km/h. This is slower than the hydrogen gas by a factor of exactly root 2.

The molecules in our vessel could orbit the Earth in just 6 hours if they were to move in a single direction at this speed. Because the motion of particles in our gas mixture is random – they jiggle about rather than move in a single direction – they stay securely in the vessel.

Conclusion after adding helium

No chemistry’s happening in the vessel – not yet. Molecules of hydrogen and helium are simply co-existing in our vessel, bouncing off each other at different speeds and not interacting in any other way.

  • Hydrogen gas, H2(g): 1.00 mol
  • Helium gas, He(g): 1.00 mol

For some chemistry to happen, we’ll need to add the next element, lithium. We’ll do that next week.

Let’s add hydrogen gas

Hydrogen: a page from Theodore Gray's book, The Elements
Hydrogen: a page from Theodore Gray’s book, The Elements

I’m going to add 1.00 mol of hydrogen gas, H2(g), to our 10-litre vessel. We’ll assume that the entire experiment is carried out at normal room temperature – let’s say it’s 20°C.

How much does a mole of hydrogen cost?

Hydrogen gas is a relatively cheap element, and my one mole of H2(g) would cost less than one cent at wholesale prices. That said, the shipping, handling and service fee would be a couple of orders of magnitude greater than the cost of the gas itself, and I’d probably need to give the store about a dollar for the privilege of taking one cent’s worth of hydrogen gas.

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What does a mole of hydrogen look like?

We’ll assume the temperature is 20°C and the atmospheric pressure is 102.3 kPa, which is what the Weather app on my phone is reading right now. After the hydrogen gas has been released from its high-pressure storage cylinder, my one mole of H2(g) would have a volume of 23.8 litres at these conditions. That’s about enough hydrogen gas to fill up a party balloon.

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Hydrogen is a colourless, odourless gas that’s lighter than air. It’d float upwards very quickly if I opened the valve in the store. I’m now going to squeeze all that gas into my 10-litre vessel.

What’s the resulting pressure of the vessel?

If I squeeze that 23.8 litres of hydrogen gas into my 10-litre vessel, the resulting pressure in the vessel must be greater than atmospheric pressure (1 atm) because I’ve compressed the gas. We can calculate the final pressure precisely by using the ideal gas law: PV=nRT.

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That’s significantly higher pressure than atmospheric pressure, which varies from 100 kPa to 102 kPa under normal weather conditions.

Interestingly, the pressure in the vessel, 243 kPa, is equal to 35.2 pounds per square inch (psi), which is the same as the recommended pressure for a car tyre.

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Other than making random movements inside the vessel, the hydrogen molecules won’t really do anything else.

How fast are the molecules moving about?

We can calculate the average speed of the molecules by using the following equation:

*Note that R is the gas constant, 8.31, and M is the molar mass in kg/mol

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The molecules are travelling at about 1760 metres per second (on average).

How much distance will the gas molecules travel before they collide with one another?

For this question, we need to calculate something called mean free path. The mean free path is the average distance we can expect each molecule to travel before it collides with another molecule. Mean free path is quite long in a vacuum, and very short at high pressure conditions. One of the formulae used to calculate mean free path, λ, is shown below.

**Note that in this formula, pressure (P) must be measured in pascals (Pa)- not kilopascals (kPa). We therefore need to multiply our kilopascal pressure by 1000 to convert it from kPa to Pa.

*** Note also that d is the diameter of the molecules being studied in metres. Wikipedia tells us that hydrogen molecules have a diameter of 120 picometres. I’ve used this value in the equation below.

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The molecules in our vessel collide with each other roughly every 260 nanometres. That’s tiny: it’s just a few percent of the width of a cell nucleus!

How often do the molecules collide?

Let’s go right back to Year 10 Physics for this one. The time between collisions will be equal to the average distance travelled between collisions divided by the average speed of the molecules:

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The molecules collide with each other roughly every 0.1478 nanoseconds.

How many times do the molecules bump into each other each second?

By taking the reciprocal of the average collision time, we can find out how many times the molecules collide with each other every second, on average:

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Each molecule in our ten-litre vessel makes 6.765 billion collisions per second with neighbouring molecules.

Apart from lots of uneventful particle collisions – a total of 4.07 decillion uneventful collisions per second to be precise – not much else is happening in our ten-litre vessel at this stage.

Conclusion

  • Hydrogen gas, H2(g): 1.00 mol

Next week, we’ll add some helium to the vessel and see what happens.

Periodic Table Smoothie

periodic table by randall monroe what if.png
Image from Randall Monroe’s excellent book, What If?: Serious scientific answers to absurd hypothetical questions

Yesterday, I was wondering what would happen if we mixed the entire periodic table of elements together in a blender. Unsurprisingly, it would explode, scattering radioactive dust and debris for miles around in a red-hot fireball formed from the simultaneous fission of the entire seventh row. The periodic table would only need to be the size of a matchbox in order for this explosion to happen.

Calculating exactly what would happen would be incredibly difficult. There are so many simultaneous reactions – including nuclear reactions – taking place that it’s almost impossible to predict the outcome in any more detail than “KABOOM”.

Making a real Periodic Table Smoothie  would be prohibitively expensive. You’d need 118 particle accelerators (costing $1 billion each) all pointing at the same target just to get single atoms of each element to collide at the same time. This is even more difficult than it sounds: those elements near the bottom of the periodic table (numbers 105 and above) are so unstable that they’d break down before they even reach the target. There are massive financial and physical challenges to mixing an entire periodic table up in a blender.

Instead of adding all the elements at the same time, I’ll be adding one element each week to an imaginary 10-litre vessel and documenting – as a theoretical exercise – what happens. Ultimately, we all know it’s going to explode at some point. But when will it do that? How many elements are we able to add before it finally explodes? Will we create anything interesting along the way?

This very idea was floated on Reddit’s AskScience forum in 2013 but nobody actually figured out (seriously) what would happen.

Join me next week to start the experiment.

periodic table smoothie on reddit.jpg

 

What if we put 200 g ice into 1.00 L hot water?

Ice + water --> ice water
How much of a chill will these ice cubes give to a bucket of hot water?
Today, we’re going to answer the following question:

When 200 grams of ice is added to a bucket containing 1.00 litre of hot water, what’s the final temperature of the water?

To answer the question, we’re going to need to make some assumptions. We’ll take 1.000 litre of pure water at 80.00°C and add 200.0 g of ice (at -10.00°C) to it. What’s the final temperature of the water?

Part 1: Heat transfer method

The following equation can calculate the temperature at thermal equilibrium of any number of objects in thermal contact.

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I love this equation because it’s several lines of maths shorter than the version taught in school. With this equation, you don’t even need to convert the temperatures into kelvin. Celsius works just fine.

Let’s set up the equation so that the addition series contains the variables in the question.

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Now, let’s substitute the gives values into the equation. The specific heat capacity of water is 4200 J kg-1 K-1, and that of ice is 2100 J kg-1 K-1.

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Great! Adding 200.0 g of ice to 1.000 L of water decreases the temperature from 80.00°C to 71.80°C.

But we’ve forgotten something. The ice will melt as soon as it hits the hot water. Since melting is an endothermic process, heat energy from the water will actually be absorbed, thus reducing the final temperature even further.

Part 2: Let’s take into account the fact that the ice melts!

Remember our formula from part 1.

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The amount of energy required to melt ice can be calculated using the latent heat equation:

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Removing that amount of heat energy from the system results in the following equation:

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Great! Now, we’ve calculated that the final temperature of the water would be 57.36°C after the addition of the ice. That’s equal to 330.5 kelvin, which will be useful later.

However, we’ve forgotten to take something else into account: how much heat will be lost as radiation from the surface of the bucket?

Part 3: What’s the rate of heat loss from the bucket by radiation?

The rate of heat lost by radiation can be calculated by using the Stefan-Boltzmann equation, below.

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P is the rate at which heat energy is radiated from the surface of the bucket in watts. Emissivity, e, of water is 0.95, and the surface area, A, should be around 0.0707 m2 for a one-litre bucket. Calculation of A is shown below. Assuming that the radius of the surface of the bucket is 6cm:

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Plugging that value into the equation, we can find P. We’ll assume that the experiment is being conducted at room temperature and the temperature of the surroundings is 20.00°C (29.03 K).

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This means that 2.928 joules of energy are emitted from the surface of the bucket every second. Ten minutes later, the bucket would have lost 1756.8 joules of energy due to radiation from the surface. But what about emission of radiation from the sides of the bucket?

Let’s say that our bucket is made from highly polished aluminium (which has emissivity 0.035) and it holds exactly 1.2 litres of water. We need to calculate the dimensions of the bucket.

Assuming it has straight sides (i.e. it’s a cylinder), the bucket had volume equal to the following formula:

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The surface area of our bucket (excluding the open surface at the top) is:

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The rate of energy radiation from the sides would therefore be:

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It’s interesting to note how very little radiation is emitted from the shiny aluminium bucket, while lots more radiation is emitted from the surface of the water. This is because relatively ‘dark’ water has a much higher emissivity than shiny aluminium. Total emission from the bucket is therefore:

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After ten minutes, the bucket would have lost the following amount of energy:

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Let’s factor this amount of energy loss into our final temperature equation.

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Not much energy is lost via radiation! Finally, let’s find the peak wavelength of the radiation emitted by the object using Wien’s law.

Part 4: What’s the wavelength of the radiation being emitted by the bucket?

Here’s Wien’s law from Unit 1 Physics…

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The radiation emitted from the resulting bucket of water lies firmly in the infra-red part of the electromagnetic spectrum. The bucket would be clearly visible on an infra-red camera!

Next week, we’ll begin a new a Chemistry-themed project called Periodic Table Smoothie. More next week.

Shut off Your Digital Screens by 9PM

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Your iPad screen might be stopping you from getting a good night’s sleep

Sleep is an essential part of our development and wellbeing. It is important for learning and memory, emotions and behaviours, and our health more generally. Yet the total amount of sleep that children and adolescents are getting is continuing to decrease. Why?

Although there are potentially many reasons behind this trend, it is emerging that screen time – by way of watching television or using computers, mobile phones and other electronic mobile devices – may be having a large and negative impact on children’s sleep.

It has also been suggested that longer screen times may be affecting sleep by reducing the time spent doing other activities – such as exercise – that may be beneficial for sleep and sleep regulation.

Screen time in the hours directly prior to sleep is problematic in a number of ways other than just displacing the bed and sleep times of children and adolescents. The content of the screen time, as well as the light that these devices emit, may also be responsible for poorer sleep.

The content, or what we are actually engaging with on the screen, can be detrimental to sleep. For example, exciting video games, dramatic or scary television shows, or even stimulating phone conversations can engage the brain and lead to the release of hormones such as adrenaline. This can in turn make it more difficult to fall asleep or maintain sleep.

The number of devices and amount of screen time children and adolescents are exposed to is continually increasing. Given these early associations with reduced sleep quality, and the importance of sleep in healthy development and ageing, this is an issue that is not likely to go away any time soon.

Sleep should be made a priority, and we can combat this growing problem in a number of ways.

Tips for getting a better night’s sleep

  1. Limit screen time within the two hours before falling asleep
  2. Remove computers and mobile devices from the bedroom
  3. Use iOS Night Mode (available on iOS 9.3 and later)
  4. Use Flux for Mac
  5. Limit screen time for children under 13 to just two hours per day

Subscribe to my Apple News Channel

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Subscribe to this website via Apple News (requires iOS 9 and above)

I was recently accepted as a contributor to Apple News. This means that readers can now access this website’s content via the Apple News app from any iOS device. The latest posts will appear directly in readers’ Apple News feeds. This is quicker and much more convenient than using the mobile version of this website.

I’ve been using Apple News for a while now, and I love having quick access to important news from various sources. You can customise which news sources you want to appear in your news feed: there are around 2000 news sources to choose from, and this website has now been added to the mix.

Click here to check out my Apple News channel.

James Kennedy, Monash Apple News Channel
My Apple News channel as of March 2016. Click to subscribe.

Subscribe to Chad Jones’ New Chemistry Podcast

collapsed wavefunction logo
New podcast ‘Chemical Dependence’ is hosted at The Collapsed Wavefunction

I first came across Chad Jones when I did an interview with him on The Collapsed Wavefunction back in 2013. We discussed ingredient labelling, chemophobia and my motivations for making the Ingredients of an All-Natural Banana poster series.

Chad Jones works at Intel Corp. in Utah, USA. He’s the founder and chief science writer for The Collapsed Wavefunction, a science advocacy podcast featuring episodes on science instruction, science in popular culture, and current science news items.

In 2016, Chad’s launched his latest venture in chemistry outreach with a fantastic new podcast called Chemical Dependence. In each of the podcast’s punchy, 5-minute episodes, Chad explores interesting chemical compounds and how they’re used in society. The podcast is a great source of interesting facts to liven up any chemistry lesson. All Chemistry teachers should subscribe!

He’s even teamed up with Andy Brunning from Compound Interest for his latest episode on pipeline. Check it out here.

Check out all the episodes and subscribe to the podcast on iTunes here. Support the podcast via Patreon here.

Turn Off Social Media While Studying

A new survey shows that social media is the biggest distraction students face while studying
A new survey by Stop Procrastinating shows that social media is the biggest distraction students face while studying

The leading internet blocker, Stop Procrastinating, has announced that 64% of US students have cited online distractions such as social media as a hindrance to their productivity. Facebook, Twitter, Snapchat, shopping websites and YouTube were among the sites that students found the most distracting.

Fear of Missing Out (FOMO)

Nearly all of the students who responded in the survey referred to a ‘fear of missing out’ (FOMO), which is the anxiety that people experience when they believe that important events are happening without them. The anxiety arises from a perceived decrease in ‘popularity’ if they’re not up-to-date with the latest happenings in their social circle. Teenagers are particularly susceptible to FOMO, and 24-hour social media feeds such as Facebook and Twitter are exacerbating the problem. Students are constantly checking their social media feeds (sometimes a few hundred times per day) in order to keep up with the latest drivel happenings.

Interestingly, first year university students were the most affected. It’s possible that in first year (sometimes called “freshman year”), people’s social circles haven’t quite cemented since the upheaval of leaving high school. People are therefore more anxious and fear missing out on new friendships and events… so they gravitate towards social media.

Almost half students surveyed admitted to losing an hour each day to social media. Common Sense Media estimates the real figure (including traditional media such as TV) is more like 9 hours per day. That’s a lot of screen time, and it’s affecting students’ social lives, their grades and their sleep.

Over half of the respondents said they’d been stopped from writing an essay because they felt compelled to check social media at some point. Any issue that’s stopping half of our students from writing essays (or concentrating for any extended period of time) needs to be addressed urgently.

This problem needs to be addressed urgently

The level of distraction today is unprecedented. We all carry televisions and music players in our pockets. I got in touch with Tim Rollins, the director of Stop Procrastinating, who said:

“We have made Stop Procrastinating free today in order help students to beat their Internet distractions and boost their performance in their studies. The Internet, social media, emails are pervasive and eating into our quality time. We need urgently to put ourselves back in control.” – Tim Rollins

Software is one of the tools that can help students get the lasting willpower they need to overcome FOMO and get back into studying. Here are my tips for eliminating distractions while studying.

Tips for distraction-free studying

  1. Delete all the Facebook apps from your phone
  2. Study with your phone in aeroplane mode
  3. When using your desktop, use the Stop Procrastinating app to limit your access to social media sites.
  4. Study without music. All the research says it doesn’t help.
  5. Don’t eat and study at the same time.
  6. Drink only water while you’re studying.
  7. Sit upright while studying: don’t study laying in bed or leaning back on the couch.
  8. Have a goal for each study session. Write it down and work until you’ve completed it (e.g. make notes on all 6 types of acid/base chemical reactions with examples)
  9. Study in a location that you never use for relaxation… the library is a great choice. Most students can’t study in their bedroom because they usually relax there.
  10. Limit the number of Facebook friends to 30. Delete all the others: I understand this takes some courage, but you probably don’t know them anyway! Their unimportant updates distract you from studying.

Stop Procrastinating is an Internet blocking and productivity application compatible with OS X and Windows. It allows users the option to block the Internet for a period of time in three ways, depending on how much self-discipline they have.

Combining Chemicals And Students Safely

Chemistry lab. Image supplied by National Laboratory Sales
Image supplied by National Laboratory Sales

In science education, chemistry is one of the disciplines that involves regular hands-on work in a laboratory. While teaching students the intricacies of chemistry presents no exceptional risk, the very real dangers posed by many chemicals demand a higher level of safety consciousness and preparedness. This general overview outlines sensible security precautions for high school and college chemistry labs.

The Importance Of Documentation

Fortunately, in a classroom setting, all of the chemicals being used will be well understood. This means information on their potential risks is widely available. This information must be used to ensure that each substance used is treated with the proper respect for the dangers it poses.

The first source of information for any chemical is the label it carries. These always describe their hazards, but labeling may be incomplete. A more authoritative source for hazard information is the material safety data sheet (usually referred to as an MSDS) for the substance. A comprehensive reference collection of MSDSs is an integral part of every laboratory, and this collection needs to be freely available to all teachers using the classroom’s chemical supply.

Equipment And Facilities

At the high school or college level, chemistry experiments demand their own dedicated laboratory spaces. These labs should meet all state and national safety requirements and cannot be used for teaching other subjects. Even the scheduling of laboratory use must be geared towards safety. Adequate free periods must be included every day for cleaning the lab and disposing of chemicals.

Chemicals need a dedicated, lockable storage room equipped to contain them safely. A prep room is also required for teachers to use. This needs equipment similar to the lab room albeit on a smaller scale. For all three of these spaces, ventilation is a critical concern. Ventilation hoods should be used in the lab itself and all of the air removed from the lab must be vented outside.

Full safety equipment needs to be available for everyone in the laboratory while chemicals are in use. This includes both permanent safety facilities (e.g. eyewash stations, first aid kits, etc.) and personal protective equipment (PPE), including goggles. Goggles for use in chemistry labs must conform to stricter standards than other forms of eye protection to ensure that they protect against both flying debris and liquid splashes.

Planning And Preparing

Every chemistry lab needs thorough safety plans for both general and specific chemical risks. While standardized materials including the safety documentation discussed above can be used to prepare safety plans, each teacher responsible for leading classes in the lab has a responsibility to set out his or her own safety measures.

Customized safety preparations should take the specifics of the facility and the coursework into consideration. Methods for calling for help, evacuating the lab, and documenting incidents will vary based on the layout of the facility and its resources. By designing their own safety plans, teachers will be better prepared to enact them in the event of an accident.

The Teacher’s Role

A chemistry teacher has many responsibilities beyond instruction and safety planning. One of the most important of these responsibilities is teaching his or her students to share a healthy respect for the hazards posed by chemicals. Teaching and testing them on basic safety precautions and lab-specific emergency procedures is just a start.

Students should learn to understand the intricacies of chemical labeling before working with hazardous chemicals. (For example, the terms danger, warning, and caution are each distinct, indicating decreasing levels of risk.) At the college level, where students may be working independently and designing their own experiments, teaching them to read the MSDS is strongly recommended. For younger students teachers can often make use of intermediate-level warning documentation (e.g. CLIPs, Chemistry Laboratory Information Profiles) to give them adequate chemical reference materials.

Keeping students safe in the laboratory is not a difficult job. It requires a heightened sense of awareness and an amount of preparation commensurate with the hazards posed by the chemicals involved. When preparedness is combined with proper facilities, equipment, and training, schools labs can be safe places to learn through direct experimentation with all but the most dangerous of chemicals.

Whether you’re building a new Lab or upgrading your existing one, you will find a remarkable selection of Casework, Workstations, Fume Hoods and related lab products at National Laboratory Sales.

The Psychology of Chemophobia – Part 5

Bananas contain unpronounceable ingredients, too. Ingredients of an All-Natural Banana by James Kennedy
Bananas contain unpronounceable ingredients, too

What is chemophobia?

The scientific community describes chemophobia as a “non-clinical prejudice” – rather like homophobia or xenophobia – that is, not a true medical phobia but a learned aversion to ingredients created in laboratories. Researchers Paul Slovic and Baruch Fischhoff identified a number of affective characteristics that help to explain deep and persistent overestimation of chemical risk. They found that people tend to overestimate human-made risks, and underestimate natural risks.

On Artificial Formaldehyde

The most dangerous consequence of this quirk is people’s fear of formaldehyde. Formaldehyde is a naturally-occurring compound that is found in fruits such as peaches and pears, vegetables, meat, eggs and foliage, and is found in very high concentrations in Peking duck, smoked salmon and processed meats (e.g. ham and sausages). These so-called ‘natural’ sources of formaldehyde are usually considered acceptable by the public, while artificial sources of formaldehyde such as vaccines and baby shampoo, have caused public outcry.

“People tend to overestimate human-made risks, and underestimate natural risks.” – Slovic & Fischhoff

One such outcry forced Johnson’s to undertake one of the biggest reformulations in history, and remove all traces of formaldehyde from its products. This was despite the fact that there was so little formaldehyde present in their baby shampoo that you’d need to take 40 million baths per day to reach dangerous levels. Johnson’s spent tens of millions of dollars on a reformulation project not because they were legally obliged to, and not because there was ever a safety risk, but because they were under pressure from irrational consumers to change their recipe. I call them irrational because nobody ever petitioned for an expensive reformulation of smoked salmon, Peking duck, peaches or pears because of formaldehyde fears.

Vaccines also contain tiny amounts of formaldehyde. Irrational fear of ‘artificial’ formaldehyde has led some people to avoid vaccinations altogether even though the level of formaldehyde found in a vaccine is 80 times less than in a single pear. People’s irrational fear of formaldehyde has caused many preventable deaths; anti-vaccination movements have caused measles outbreaks in California (2015), Germany (2015), Wales (2013) and other places.

Chemophobia is the irrational fear of chemicals, particularly artificially-created chemicals

People overestimate risks that are imposed on us, like contaminants and pollutants, than risks we engage in voluntarily

Another reason people fear formaldehyde in vaccines (but not in pears) is because humans are irrationally hard-wired to overestimate the magnitude of risks that are imposed upon us. Most people over-fear terrorism and under-fear obesity. Terrorism killed 32,000 people in 2015, yet obesity kills tens of millions of people each year. Despite that, terrorism remains a key subject in American presidential debates because people’s fear of terrorism is inflated out of proportion by the fact that it’s imposed on the public rather than being caused by the public themselves. Americans are 33,000 times more likely to die from a heart-related disease than from terrorism, yet terrorism tops people’s list of fears due to the irrational quirks of human risk perception.

We all are born with these afflictions, and only science education can help us overcome them

The psychology behind these irrational assumptions is innate and is present in all of us. It’s only with science education and a basic knowledge of toxicology that we can begin to assess the risks associated with different compounds in a meaningful way. Only science education can fight chemophobia and allow people to make rational decisions about healthcare, skincare and nutrition.

This post is part 5 in a weekly series about chemophobia. Not only are people less afraid of natural toxins than synthetic ones, but in some cases, safety legislation is more lenient when it comes to natural threats vs artificial ones. Next week, we’ll explore some specific examples of toxins that are present (naturally and artificially) in the foods we eat.

(Almost) Nothing is Truly ‘Natural’ – Part 4

Cezanne nothing is natural fruit and vegetables painting still life
Nothing on this table is natural – not even the fruits. The Basket of Apples by Cézanne

Corn isn’t ‘natural’

In 2014, I created a series of infographics to help convey this message. Corn, for example, used to be a spindly grass-like plant called teosinte, which Native Americans farmed and bred through artificial selection until it resembled the yellow corn of today.

In 9000 years, sweetcorn has become 1000 times larger, 3.5 times sweeter, much easier to peel and much easier to grow than its wild ancestor. In the 15th century, when European settlers placed new selection pressures on the crop to suit their exotic taste buds, the corn evolved even further to become larger and multi-coloured. Corn no longer resembles the original teosinte plant at all.

Watermelon isn’t ‘natural’

Watermelon began as a hard, bitter fruit the size of a walnut. It caused inflammation and had an unpalatable bitter taste. Thousands of years of artificial selection (unintentional genetic engineering) have resulted in a modern watermelon that bears no resemblance to its African ancestor. Modern (artificial) watermelons are sweeter, juicier, more colourful and easier to grow than their ancestral varieties.

Peaches aren’t natural, either

Peaches used to be hard, cherry-sized fruits with giant pips. Like corn and watermelon, peaches became larger, sweeter and juicier over thousands of years of inadvertent genetic engineering.

Bananas, wheat, pigs and all farmed animals and plants are not natural

Before agriculture, carrots were white and spindly. Wheat was tall and scrawny with little calorific value. Apples were tiny and sour with giant pips (like crab-apples today). Strawberries were tiny, bananas had stones in them, and pigs were viscous creatures with tiny backsides that made for a not-so-delicious ham. Cows didn’t produce much milk (just enough for their own calves) and chickens were skinny little creatures that laid eggs weekly rather than daily. Every species that’s ever been farmed by humans has been genetically modified over time as a result.

I keep making this point because our ancestors deserve credit for their hard work: they toiled in the fields for thousands of years to breed plants and animals that are suited to our modern tastes and lifestyles. For modern humans to call the results of our ancestors’ hard work ‘natural’ is an insult to the millions of ancient farmers who worked so hard to produce them.

Engineers (including genetic engineers) know that humans have toiled for millennia to change nature and suit it to our own needs – animals became tamer and meatier, and plants started producing more edible portions. I want to counteract the misconception that humans encountered nature in a ‘pristine’ state.

Great documentary snippet – Animal Pharm

[ancient humans] toiled in the fields for thousands of years to breed plants and animals that are suited to our modern tastes and lifestyles. For modern humans to call the results of their hard work ‘natural’ is an insult to our ancestors.

I show the above documentary my Year 10 Science students to demonstrate what is currently being produced using genetic engineering techniques. The video explains all the concepts mentioned in this article and is accessible for and educated audience of any age.

This post is part 4 in a weekly series on chemophobia. Next week, we’ll look at the psychology behind chemophobia.

On the $$$ fuelling Chemophobia – Part 3

We’ve already asserted that chemophobia is an irrational psychological quirk that gained traction after the environmental movement of the mid-1960s. But I don’t want to make such allegations without proof. In part 3 of this weekly series on chemophobia, I’ll show you some of the irrational conclusions that chemophobia leads us to make, and the psychology that lies behind them. We’ll also look at some examples of companies that are using chemophobia with maximum leverage to inflate the prices of foods and skincare products in stores.

People perceive products with moral claims on the packaging as more effective than those without

Boyka Bratanova at Abertay University offered participants a choice between two cookies: one was normal, and another was labelled “organic/locally-produced/carbon-neutral”. The cookies were otherwise identical.

people believe these organic cookies taste better

Amazingly, when the participants were asked specifically to evaluate the taste of each cookie, they consistently rated the ‘morally-superior’ cookies as more delicious. Bratanova’s study confirms Meng Li’s hypothesis (discussed last week) that people confuse moral claims with actual superiority. Manufacturers are taking advantage of this psychological trick by writing meaningless claims of moral superiority such as “natural”, “pure” and “free from {insert harmless ingredient here}” on their product labels to justify price increases at the point of sale.

The global market for ‘natural’ and ‘organic’ personal care products is projected to reach US$16 billion by 2020. But are these ‘natural/organic’ products really any better than their non-organic equivalents? Evidence suggests not.

Take Gaia Natural Baby Skin Soothing Lotion, for example, which sells for 4.4 cents/mL in Coles. A comparable ‘normal’ product, Johnson’s Baby Lotion, sells for just 1.7 cents/mL. Gaia can charge its customers 2.5 times the price compared with traditional Johnson’s Baby Lotion largely because it claims “Pure, Natural, Organic” in large text on the front of the bottle. Unfortunately, these claims aren’t actually true (and this product was recalled in December 2015 because of its ‘inaccurate product label’; read more here).

Gaia makes these three misleading claims on all of its products
Gaia makes these three misleading claims on all of its products

“Pure” is a claim reserved for single-ingredient products only

By definition, mixtures such as baby lotion cannot be ‘pure’. Pure substances contain only a single ingredient (e.g. pure salt, pure white flour, pure cane sugar and pure spring water). No cosmetic or skincare product should ever be labelled ‘pure’.

“Natural” products must be sold as they’re found in nature

Very few products are truly natural. Not only is the definition vague, but there are no enforceable regulations on its use in Australia, New Zealand or the US. The Food Standards Agency in the United Kingdom proposes some guidelines: “made from natural ingredients that have not been interfered with by [humans]”. Again, it’s impossible for any cosmetic or skincare product to be totally natural. All cosmetics and skincare products have been ‘interfered with’ by humans, and they the vast majority of skincare products contain artificial ingredients.

“Organic” only makes sense when applied to foods

Adding a couple of drops of ‘organic’ ingredients into your product to justify writing “organic” on the label should be illegal. But that’s exactly what Gaia has done: the ingredients certified ‘organic’ in their Natural Baby Skin Soothing Lotion amount to approximately just 7% of the product.

Because ‘organic’ is a farming technique, farmed foods are the only products that should ever be labelled ‘organic’. It’s impossible for cosmetics and skincare products to be ‘organic’ because many of the ingredients (even in self-proclaimed ‘natural’ brands such as Gaia) are artificially synthesised rather than grown.

Consumers are being tricked into paying a higher price for a product that isn’t necessarily superior.

Natural chemicals can be harmful, too (and the most harmful compounds on Earth are all natural)

Gaia’s “all-natural” baby lotion was recalled because it contained undisclosed allergens. Nine out of the top ten most dangerous compounds on Earth are naturally-occurring. When it comes to skincare, synthetic compounds are often gentler and more suited to their purpose than are their natural counterparts.

Natural compounds are sometimes far more dangerous than synthetic ones. Blue, artificial compounds; green, naturally-occurring compounds.
Natural compounds are sometimes far more dangerous than synthetic ones. Blue, artificial compounds; green, naturally-occurring compounds.

Some studies even suggest that crops on organic farms produce more pesticide within the leaves in order to protect themselves from increased rates of insect predation. Some of these natural pesticides are actually more potent skin irritants than the synthetic pesticides used in conventional farming methods.

In addition, organic crops can be sprayed legally with many pesticides, some of which are potent irritants. Lists of pesticides approved for use on organic farms can be found here and here. There exists a misconception among consumers that organic produce is ‘pesticide-free’, which is a concern considering that ‘no pesticides’ is the most common argument heard in favour of buying organic produce.

Consumers are being tricked into paying a higher price for a product that isn’t necessarily superior, and still might contain harsh (natural) compounds that irritate their skin.

Many brands are making these misleading claims…

Some of Sukin's "fragrance-free" products contain fragrances such as sesame oil and rose hip oil
Some of Sukin’s “fragrance-free” products contain fragrances such as sesame oil and rose hip oil
Envirocare's hair cleanser made extreme 'natural' claims before it was recalled by the Australian Government. Source: recalls.gov.au
Envirocare’s hair cleanser made extreme ‘natural’ claims before it was recalled by the Australian Government. Source: recalls.gov.au
Mustela's milky bath oil claims to be 'natural' but contains mostly artificial ingredients
Mustela’s milky bath oil makes a vague claim about having ‘natural ingredient [sic]’ but contains mostly artificial ingredients e.g. PEG-6 isostearate and propylene glycol
Sukin makes claims that aren't even relevant to the product being sold. Moisturisers are labelled "SLS-free", for instance. SLS should never be in a moisturiser!
Sukin makes claims that aren’t even relevant to the product being sold. Moisturisers are labelled “SLS-free”, for instance.
Sometimes, the ingredients labels make no sense whatsoever. They've put a 'word salad' instead of actual ingredients on this one. This product should be recalled or over-labelled immediately.
Sometimes, the ingredients labels make no sense whatsoever. They’ve put a ‘word salad’ instead of actual ingredients on this one. This product should be recalled or over-labelled immediately.

Update: Gaia has recalled the product above due to its ‘inaccurate product label’

Their signature baby lotion is being withdrawn from sale due to an undisclosed ingredient labelling problem… Gaia was unable to provide any further information and declined to comment on the issue.

Gaia has recalled the product mentioned in this article due to the presence of undisclosed allergens
Gaia has recalled the product mentioned in this article due to the presence of undisclosed allergens. Source: recalls.gov.au

On the Pervasiveness of Chemophobia – Part 2

Bill Gates drinks water purified from sewage at Seattle's Omniprocessor plant
Bill Gates drinks water purified from sewage at Seattle’s Omniprocessor plant

Would you drink water that’s been purified from sewage? Bill Gates did:

“It’s water,” he says. “Having studied the engineering behind it… I would happily drink it every day. It’s that safe.” – Bill Gates

He’s talking about the Omniprocessor in Seattle, USA, which illustrates perfectly the prevalence of chemophobia in our society. The Omniprocessor takes sewage waste and purifies it into clean drinking water. The dried sewage is then combusted to power the plant, producing electricity that can be sold back to the grid. Essentially, it’s a free sewage disposal system that also gives you clean drinking water and a plentiful supply of electricity. Omniprocessors could be a huge income boost for farmers in developing countries.

The plant in Seattle was met with resistance. One study showed that 26% of survey participants were so disgusted by the idea of “toilet-to-tap” that they agreed with the statement: “sewage water could never be purified to such an extent that I would be willing to drink it”. Try it yourself: which glass of water would you rather drink?

We all feel a slight preference for the glass on the right. Chemophobia, an irrational psychological quirk, is more prevalent than you might think.
We all feel a slight preference for the glass on the right. Chemophobia, an irrational psychological quirk, is more prevalent than you might think.

If science tells us the purified sewage-water is perfectly clean, then why aren’t people comfortable with drinking it?

Instinct: Once contaminated, always contaminated

Paul Rozin at the University of Pennsylvania provides an explanation. He uses the term “contagion” to describe the perceived, permanent grossness that objects or substances acquire once they have touched something disgusting. No amount of purification can remove the ‘disgust factor’ that’s been acquired by the object. It’s purely psychological, and has no basis in science, but might have evolved as a useful behavioural adaptation that protects us from disease.

Mark Schaller at the University of British Colombia coined the phrase “behavioural immune system” to describe this phenomenon. It includes a suite of feelings and behaviours, including repulsion and disgust, that prevent us from eating contaminated food. It’s overly sensitive, and is at the root of many culinary taboos (e.g. don’t eat pork/prawn/insects).

All of this makes evolutionary sense: for millions of years of human evolution, we had no way of purifying food once it had become contaminated. We had no way of boiling water (and no fire) for 90% of human history. We had no modern medicines for 99% of human history, which made even small illnesses a horrifying, life-threatening prospect. Paranoia about cross-contamination has probably saved our species from extinction.

So why do some people see ‘synthetic chemicals’ as contaminants?

Science teachers are partly to blame. I tell my students never to eat in the lab because we’re fearful of contaminating the student’s food with lab chemicals, which might make them ill. I tell my students never to pour back into the stock solution because we might contaminate the stock solution, ruining future experiments. When an unidentified clear liquid (either pure water or a highly corrosive acid) splashes onto a student’s skin, I tell them to assume it’s the highly corrosive acid and wash immediately with copious amounts of water, just in case. Science teachers inadvertently instil in students a fear that laboratories are highly contaminating places. We do this with the absolute best of intentions.

Science teachers contribute to the notion that labs are full of contaminants.

Paranoia about contamination in laboratories has likely prevented countless accidents worldwide. It’s saved lives and limbs, too, and that’s why teachers must keep emphasising these safety messages. In doing so, however, do need to be mindful of the the unfortunate side-effect of ‘contagion’, which is the gut instinct that foods and lotions (or even water) created in a lab must be contaminated with something nasty. We need to counteract that notion in the following way.

We must emphasise purification techniques in school

When my students made aspirin last week (about 8 tablets’ worth), I told the students we cannot ingest the aspirin because “it’s contaminated: it contains unknown impurities”. Similarly, when we made esters last term (edible artificial flavourings), I told the students not to touch the esters or smell them too closely because they “contain contaminants such as highly corrosive sulfuric acid”. These safety warnings are valid and necessary – they’re actually a legal requirement of my job.

In industry, however, both aspirin and esters (and everything else) would be purified after production to a very high standard (usually 99.99%) before being certified safe for human consumption. Generally, however, high-school chemistry students don’t learn about purification techniques – not even in theory – so for them, the laboratory remains a dangerous place where dirty, contaminated things are created. Inadvertently, that’s become the take-home message from high-school science.

“…for [students], the laboratory remains a dangerous place where dirty, contaminated things are created.”

Purification techniques such as fractional distillation, centrifugation, recrystallisation, affinity purification and liquid-liquid extraction are all beyond the scope of a high-school chemistry course. Water purification and extraction of substances using supercritical carbon dioxide (scCO2) are in the Year 11 textbook, but these topics are not taught by many schools. Students don’t need to know the details – but they do need industrial relevance built into their course, and they need to be made aware that many of the products we use were made or designed in labs. Most importantly, they need to know that these products were purified to a high standard before being put to use.

People go for ‘natural’ products because they try to avoid potential contaminants from the laboratory

After years of hearing these messages in school, it’s no surprise that some people are so averse to eating foods or using products made in a lab. As one of my survey respondents put it so succinctly:

“If I can’t eat in a lab due to fear of contamination, how could food made in lab possibly be safe to eat? If I have been taught to treat every lab chemical that gets onto my skin as potentially corrosive, how could a moisturiser made in a lab from synthetic ingredients ever be good for my skin? This goes against what I’ve been taught throughout school!”

Science education in schools might just be one of the root causes – and one of the solutions – to the widespread prevalence of chemophobia. More next week.

This post is part of a weekly series on chemophobia. Read part 1 here.