An attempt to answer one of life’s big questions with today’s graphic - why does bacon smell so good?

(Also, setting aside some time to respond to asks in the next few days, as I’ve been a bit busy this week. If you’ve sent one through, don’t worry - they’ll all get a response.)

Also also… kudos to freshphotons for the idea for this aroma chemistry series!

As the Periodic Table graphic’s taking a little time, here’s a peak at how part of it’s currently looking. Very much still a work in progress - the sharper-eyed amongst you will probably noticed there’ve already been a few tweaks from the initial key I posted a short while ago. 

The categories for each element are: melting point (blue, ˚C); boiling point (red, ˚C); Pauling electronegativity (purple); density (green, g/cm3 for solids, g/L for gases); first ionisation energy (pink, kJ/mol); and radius (orange, empirical, Å).

Hoping to have it finished within the next few days!

could you set fire to the moon?

Interesting question!

For a fire, we’d need oxygen, fuel and heat. First off, let’s consider the atmosphere of the moon. We usually think of the moon as being surrounded by vacuum, but it does actually have a very thin atmosphere - it’s less than one trillionth of the density of Earth’s atmosphere (at sea level). The gases in this atmosphere come from the radioactive decay of elements in the crust of the moon, and also from the solar wind. The reason we don’t consider it to have an atmosphere, is because it has to be constantly replenished by these sources - the gases are continually being lost to space.

The composition of the atmosphere isn’t well known, but it’s estimated to be around 80,000 atoms per cubic centimetre. Of these, around 40,000 are argon, 2,000-40,000 are helium, 70 are sodium & 17 are potassium; small amounts of oxygen have been detected, but this is a very small proportion. Since fire needs an atmosphere of around 16% oxygen to burn, the moon’s atmosphere wouldn’t contain enough.

As far as fuel goes, we’d also be struggling. The moon’s crust is made of a variety of oxygen-containing compounds. The major compounds are silica (SiO2, ~45%), alumina (Al2O3, ~15-24%), calcium oxide (CaO, ~12-16%), iron oxide (FeO, ~6-14%), and magnesium oxide (MgO, ~7.5-9%). This mixture of compounds is non-combustible, so wouldn’t be able to act as a fuel for our fire, even if we could somehow provide enough oxygen and heat.

So, in short, you couldn’t (easily) set fire to the moon!

All of the ‘Colourful Chemistry’ graphics so far are now available on the site as one download:

handsoffire asked:
What's the deal with monosodium glutamate? I've heard that the glutamic acid in it isn't toxic as it has been believed, but I also hear that it is used to make lab rats gain weight. What's going on chemically and is it safe?

Glutamates add an ‘umami’ flavour to foods, which is a Japanese word essentially meaning ‘pleasant savoury taste’. It’s naturally found in a wide range of foodstuffs - a few examples are meats, parmesan & tomatoes, amongst many others. 

When you add salt to a dish, you obviously perceive the taste as salty. When you add MSG, you’re also stimulating the taste receptors on your tongue, but in this case those that respond to the ‘umami’ flavour.

MSG was in the past linked to migraines, hypertension & heart disease - to be fair, it still is if you do a quick google search. This kicked off when a Doctor wrote in a scientific journal (not specifically about MSG) that he experienced uncomfortable symptoms after visiting Chinese restaurants. From this rather ambiguous anecdote came ‘Chinese Restaurant Syndrome’, which was (incorrectly) linked specifically with MSG.

Some research on rodents showed that MSG could have unpleasant effects - but this research was carried out using ridiculous amounts of MSG per kg of body weight, far more than a human would comparably consume. One test used 20g per 100g of rat food - a huge amount when you consider that the average consumption figure for UK adults is around 4g a week.

A review of the research in 2006 found that there was no consistent clinical data to support the claims that MSG caused a variety of conditions. All countries that have any form of food licensing department have passed MSG as safe at normal dietary levels. So, MSG really gets a horrendously bad rep for no good scientifically proven reason. Neither glutamic acid, or MSG (the sodium salt of glutamic acid) are in any way toxic at levels regularly consumed.

Hope that makes it a bit clearer!

Back to basics today, with ‘A Brief Guide to Types of Organic Chemistry Formula’:

Anonymous asked:
Help! I am so incredibly terrible at balancing chemical equations and I'm in honors science and its caused me to drop from a 96% to an 81% any advice or tips??

A lot of people have trouble with balancing equations, so I’m going to explain how I teach them in the hope it might help a few people. I don’t know if it’ll work for you, but I teach my pupils how to balance them using Lego. Let’s use a displacement reaction as an example:


Obviously, you can’t change any of the formulae, so I’ve boxed them off as a reminder. You can only put numbers in front of the different elements or compounds in the equation to balance it. To start with allocate a different coloured lego to each element in the equation. I’m going to use blue for aluminium, green for copper, yellow for sulfur and red for oxygen. I’m also going to use circles because I’m too lazy to draw lego. Just, I don’t know, pretend they’re Lego:

Now, that’s already looking a little more complicated. But remember, all we want to do is ensure we’ve got the same number of each element (each colour circle) on either side of the dotted line. You can see at the moment we’re short of one aluminium (blue), two sulfurs (yellow), and quite a few oxygens (red)! Since aluminium’s the easiest one to solve, let’s do that first - you just need one more blue circle on the left, so if we put a two in front of Al, that solves it:

We also need another two sulfurs. We can achieve that by putting a 3 in front of CuSO4. However, we’ve got to bear in mind that doing this multiplies all the elements in that compound by three. So, as well as ending up with three sulfurs, we’ll also get three coppers and twelve oxygens:


That turns out to have been quite useful, since we’ve now got the right number of sulfurs and oxygens. However, we’ve now got three coppers on the left, when we only have one on the right. That’s easy to fix with a three in front of copper:


And there we have our balanced equation - you can see we’ve now got the exact right number of each element (or each coloured circle/lego). Hope that method helps you!

Prototype key for a Periodic Table I’m working on. Very much a work in progress, and likely to take a little time; currently it looks like a Periodic Table for ants, so need to work on that! Also working on a series of graphics on natural poisons.

It seems Compound Interest is once again a trending blog on Tumblr, which is awesome :) Hi to all the new followers, and thanks for following! You can check out all the infographics that have previously been posted to the site right here.

The latest food chemistry infographic looks at the chemistry of cloves: a suggested remedy for toothache… and, apparently, premature ejaculation:

Anonymous asked:
Of course Sulfur is in there. (We have a running gag about sulfur being stinky in our school)

It’s definitely a pretty common culprit. Body odours? Sulfur-containing compounds. The smells of onion and garlic? Yup, sulfur-containing compounds. Asparagus urine? Oh, hi there sulfur-containing compounds. You get the idea!