We’ve already examined the functional groups that can be present in organic molecules in a previous post; here, we take a look one step further, at heterocycles. Heterocycles are hugely important in organic chemistry – they make up more than half of all known organic compounds. Caffeine is a prime example of an everyday chemical that is composed of heterocycles, as is nicotine, and there are plenty of others in pharmaceuticals and natural products we use on a natural basis. Parts of our DNA are even made up of compounds which contain heterocycles.
Today’s graphic is a whimsical look at lethal doses of chemicals we consume on a regular basis. Whilst it may be more common to view chemicals in a black and white framing of ‘toxic’ or ‘non-toxic’, the reality is more of a sliding scale of toxicity. The admission of too much of any chemical into the body can cause toxic effects, and even death – the only variant from chemical to chemical is how much is ‘too much’. For some chemicals, the amount will be very low, whilst for others, it may be almost impossibly high.
We’re heading out of this world for today’s post, to examine the atmospheric compositions of the other planets in the solar system, as well as our own. Practically every other planet in our solar system can be considered to have an atmosphere, apart from perhaps the extremely thin, transient atmosphere of Mercury, with the compositions varying from planet to planet. Different conditions on different planets can also give rise to particular effects.
This graphic is the first in a series I’m hoping to make on chemicals with potentially undeserved reputations. In it, I’ll look at the evidence and research on each, and try to come to some kind of rational conclusion as to whether or not their bad reputation amongst the general public is deserved. I thought I’d kick things off with one of the most controversial topics, particularly over in the USA: the fluoridation of water supplies.
The summer holidays are here, which means there’ll soon be crowds flocking to the coast to spend the day at the beach. The supposed benefits of ‘fresh sea air’ are commonly extolled, but its origins might not be what you think: it’s the chemical compounds produced by algae and seaweed that contribute towards its characteristic smell.
With summer approaching, so too approaches the time to stock up on repellents for the seasonal onslaught of insects hungry for human blood. There are a number of different chemicals that are responsible for the repellent effects of the various sprays or creams available – and chemistry can also offer possible explanations for why some people are just that much more attractive to the humble mosquito than others.
There are few things better than an ice cold beer on a hot day. Chances are, when you crack open a beer this summer, you probably won’t be thinking much about chemistry – but it’s the particular chemicals in beer, produced in the brewing process, that give beer both its bitterness and flavour. It’s a real chemical team effort, with several important chemical families, each contributing something different but vital to the eventual taste of the beer.
It’s been a little while since the last entry in the Everyday Compounds series, so today’s post takes a look at Sodium Hypochlorite. This chemical is likely to be found in several cleaning products in your kitchen, and additionally is one of the main compounds used to chlorinate the water in swimming pools. Here’s a look at the chemistry behind these uses, and the potential dangers.
With the Fourth of July and American Independence Day on the horizon, a somehow topical post seemed in order. Having already examined the chemical compounds that give fireworks their colours in a previous graphic, I decided to examine another important firework component here: the first chemical explosive, gunpowder, also commonly referred to as black powder.
There are a wide range of gemstones used in jewellery, with each having its own characteristic colour – or, in some cases, a range of colours. The origin of these colours has a chemical basis, and the precise colour can vary depending on the chemical composition of the gemstone. Interestingly, many minerals are actually colourless in their pure form, and it is the inclusion of impurities in their structure which leads to their colouration.