The Chemistry of Custard

Eat it on your crumble, then watch the Brainiac version. Speculate why that's possible?

Now read this article.

(Background reading on forces including shear and compression here.)

Can you imagine a material that hardens under impact, but then immediately reforms to become flexible? What uses could you make of such a material? In what situations would you apply it?

Poo

Coprolite chemistry from the Royal Society. Click on Watch the video to run the lecture.

E220

I read that E220 'can be consumed by all religious groups, vegans and vegetarians'.

But what is it? Find out what you can about this common chemical used in your food.

The tin of tomatoes I bought contains citric acid.

We know that citric acid is found in citrus fruits, with lemons and limes having a greater concentration than a strawberry. But what's it doing, added to my tin of tomatoes?

I've now found out that citric acid is manufactured industrially in great quantities for detergents, medicine, and cosmetics. (Yes! I remember making the bath bombs!) It seems to act variously as a cleaning agent, as a preservative to stop mould or bacteria growth, and to provide an acidic taste.

In the tin of tomatoes, I guess it provides the 'edge' to the taste, and helps prevent mould. Do you think it also helps prevent any reaction between tomatoes and the metal of the tin that contains them?

What can you add to my knowledge of citric acid with your research?

Try acids here (then take the quiz). Read about citric acid here. I don't understand the Kreb's cycle, but I can see it starts a new area to find out about.

On the label to your Sainsbury's hard cheese is the word Lysozyme.

Lysozyme is an enzyme.

It's used in the food industry as a preservative. I found this description from Foodditive helpful:

Lysozyme acts as a natural preservative that inhibits the growth of bacteria that lead to spoilage. It is mainly used in the cheese industry in the maturation of European cheeses, by preventing the growth of Clostridium tyrobutyricum spores which cause butyric acid fermentation leading to product loss and spoilage.

In my wandering about looking for enzymes, I also found this youtube video useful. What else can you find about enzymes or lysozyme?

Maltodextrin?

Check the supermarket shelves and make a list of products where you can see this additive listed on the label. Are there particular types of foods that have this additive?

Let's eat something with it listed (the baked beans I bought this week is a good trial!) What do you think this additive might contribute to the texture, taste or appearance of food?

But what is maltodextrin?

You can do some research on Wikipedia, Wisegeek and find a chemical company to make it.

Typing Maltodextrin into Youtube also leads to a range of videos about this chemical.

After your research, what's your view? Is maltodextrin going to kill me by Thursday?

The can of chickpeas I bought has the words Contains sulphites.

Should I worry? What are sulphites?

Scroll down here to start gathering responses to that question. Can you find any more?

One list I found in Planet Internet listed all the following numbers as sulphites: E220, E221, E222, E223, E224, E225, E226, E227, E228. The Wikipedia entry is different.

But most responses agree that sulphites are a preservative, and give a product a longer shelf life. They're also 'natural' in that they are part of your naturally occurring body.

After your research, what's your response? Are sulphites in food something I should worry about?

Chemistry in your raisin bun

Welcome, ladies, to an 8-part series, Eat your chemistry.

Buy a pack of raisin buns, eat them, then look at the ingredients. You'll see E101 is listed!

Oh no! What have you eaten! What is E101?

Research riboflavin on planet internet. Are the following true or false?

It has poor solubility in water.
It is used as an orange-red colour additive in food.
It is a member of the B vitamin family.
It plays tennis.

Can cells process riboflavin? When you see E101 listed in your raisin bun what would you recommend we do: eat it or junk it?

Find out about Calcium

Find out about calcium.

How calcium reacts with water? Uses of calcium? How calcium bonds? (Am I right to say that calcium bonds with most other elements in the periodic table?)

Or maybe find what reactions a calcium compound can give... how to fry an egg using calcium oxide and water.

The Chemistry of Concrete

'Professor Poliakoff overcomes his fear of tall ladders to observe the chemistry of concrete.'

And we know the history of concrete, yes? How the Romans used it? Find out on Wiki.

Round up

Look over the periodic table. How many elements can you describe, explain, or talk about?

Now here's the Chemical Party. Don't show it to the juniors.

8 Lanthanides and actinides

In Ellen's story, the lanthanides and actinides are the underground miners of Periodic Table Town.

They are transition metals, but keep a separate place on the Periodic Table. Can you suggest why?

The lanthanides are industrious types who provide rare metals for high-tech products. Find out about one: Neodymium.

The actinides can be dangerous as they are radioactive. But what is radioactivity?

Ellen describes uranium, for example, as 'like a big crumbly cookie. Little bits can break off easily. When as atom's nucleus begins to crumble, it doesn't drop crumbs or chocolate chips, however. It flings out protons, neutrons, electrons and rays dangerous energy'.

Does that help? You could try Youtube too for understandable answers to the question. Here is a video with animation, and a video for the discovery of radioactivity.

7 Metals

Learn these three metal names! Semi metals; true metals; transition metals.

The semi-metals (or metalloids) include silicon, Si, one of the most common elements on earth. It's extremelly versatile, as it can act like a metal to carry electricity, yet also act like a non-metal and not carry electricity.

What's SiO2? You can melt SiO2 to create fulgurites; you merely need a bolt of lightening. (Can you find out more with an Internet search?)

If you mixed other elements with SiO2, you could create jasper, agate, amethyst.

The true metals include aluminium (Al), tin (Sn), lead (Pb), gallium (Ga), indium (In), thallium (Tl), bismuth (Bi) and polonium (Po). Find out about one or more from our favourite chemists at Nottingham.

The transition metals are, in Ellen's story, the bridge that spans the left to the right side of Periodic Table Town. They include gold, mercury, iron, copper, and zinc.

Transition metals conduct electricity. Read Ellen's story of how transition metals conduct electricity by 'sharing their electrons'. In her words, if the electrons are like kids, we could say, 'You can play anywhere in the neighborhood, just don't leave the neighborhood.'

6 Noble gases and non-metals

The noble gases become heavier as you go down the column of the Periodic Table. Helium is the smallest molecule; xenon is the largest. What would you expect to happen as you filled balloons with each gas?

Do your own research too. Find out an interesting detail to share about the gases; anything about neon, argon, krypton, radon, xenon, helium?

Watch this video. And this. Could you ascribe a character to each of these elements? Maybe you could make a family from them. (The mother is the brilliant and pleasant character, obviously.)

Find out something new to you too, and share your knowledge, about these non-metals: carbon, nitrogen, oxygen, phosphorous, sulfur, selenium.

You've now seen several chemists demonstrating the properties of liquid nitrogen. You could key liquid nitrogen experiments into Youtube and see what you can find.

Here's one video, with an interesting side discussion on handling liquid nitrogen - I recall seeing chemists handling it very quickly, and have had to assume they are experienced in what they do, which is why their fingers don't immediately freeze.

5 The Alkalis and Halogens

Visit periodictable.com and find the alkali brothers on the far western shore of the periodic kingdom.

Find sodium. (Watch sodium blow up here.) Find chlorine in the halogen family. Can they be paired up? What do they produce? Read Ellen McHenry's chapter explaining the properties of sodium and chlorine.

Find the 'cousins' of the alkali brothers: magnesium and calcium. Read the chapter to find out their special bonding abilities.

Here's the flame test she refers to in this chapter.

And for review... the Periodic Table game at Funbrain.

4 More about atoms: electrons

Four rules electrons live by:

1. Spin.
2. Always try to pair up with someone of the opposite spin.
3. Get plenty of privacy - stay away from other electron couples.
4. Try to live in a perfect neighbourhood - often a group of eight.

- Thanks to Ellen McHenry.

Read the rest of her chapter to find out about the special electron properties of the noble gases. Try the activities and I'll read, The Periodic Kingdom.

Plenty of videos on atoms; try this one.

3 Atoms

Can you draw and label an atom by following these statements?

-An atom is made up of three smaller particles: protons, neutrons and electrons.

-The protons and neutrons are at the nucleus of the atom.

-The electrons are smaller, and circle the centre.

-The routes the electrons travel in are orbits.

-The proton has a positive charge.

-The electron has a negative charge.

-The neutron has no charge.

And go through these:
Video showing an electron cloud.
Video showing how electrons fit together in configurations.
The Chem4kids site on Atoms. Quiz on atomic structure.

Also:
Try the free trial on BrainPOP; see if the site is useful.
Read how to find numbers of protons, neutrons and electrons, at the Jefferson Lab.
At the same site, learn how to model an atom.
GCSE chemistry support with animations of electrons orbiting nucleus at purchon.com.

In other words, loads of stuff.

Read the Ellen McHenry chapter and try placing electrons on the Atom-izer with me. Ellen suggests using nuts as the electrons. This is a great idea and I totally recommend it.