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Colourful Chemistry Inorganic Chemistry

What Causes the Colour of Gemstones?

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┬ácan vary depending on the chemical composition of the gemstone. Interestingly, many minerals are actually colourless in […]

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Colourful Chemistry Inorganic Chemistry

Inorganic Pigment Compounds – The Chemistry of Paint

The latest in the Colourful Chemistry series looks at the inorganic compounds that give many paints their colours. This shows a limited selection of the most common compounds, and there are many others; there are also a large range of organic based pigments, which aren’t discussed here (although could possibly be the topic for a […]

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Inorganic Chemistry

Testing for Cations – Sodium Hydroxide & Ammonia Precipitates

A previous post looked at the colours of transition metals, and the origin of their colours – this graphic, on the other hand, looks at how transition metals (and some non-transition metals) can be identified by the precipitates they form with sodium hydroxide and ammonia solutions. I’m going to keep the explanation of the reasons […]

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Colourful Chemistry Inorganic Chemistry

Colours of Transition Metal Ions in Aqueous Solution

This graphic looks at the colours of transition metal ions when they are in aqueous solution (in water), and also looks at the reason why we see coloured compounds and complexes for transition metals. This helps explain, for example, why rust (iron oxide) is an orange colour, and why the Statue of Liberty, made of […]

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Colourful Chemistry Inorganic Chemistry

Metal Ion Flame Test Colours Chart

This graphic looks at the colour of various metal and metalloid ions that occur during flame tests. Most people probably remember doing this experiment in school chemistry lessons, if not with the full range of ions shown here, but for the uninitiated a brief explanation of the origin of the colours follows.

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Colourful Chemistry Inorganic Chemistry

The Chemistry of Fireworks

The colours in fireworks stem from a wide variety of metal compounds – particularly metal salts. ‘Salt’ as a word conjures up images of the normal table salt you probably use every day; whilst this is one type of salt (sodium chloride), in chemistry ‘salt’ refers to any compound that contains metal and non-metal atoms ionically […]