1109, 2014
  • Chemistry of Autumn Leaves 2018

The Chemicals Behind the Colours of Autumn Leaves

September 11th, 2014|

Click to enlarge

With autumn looming on the horizon, the leaves on some trees have already begun the transition towards the vibrant hues of autumn. Whilst this change may outwardly seem like a simple one, the many vivid colours are a result of a range of chemical compounds, a selection of which are detailed here.

[…]

2906, 2014
  • The Chemistry of Gemstone Colours 2016

What Causes the Colour of Gemstones?

June 29th, 2014|

Click to enlarge

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 their pure form, and it is the inclusion of impurities in their structure which leads to their colouration.

[…]

404, 2014
  • Colourful Chemistry - Colours of pH Indicators

The Colours & Chemistry of pH Indicators

April 4th, 2014|

Click to enlarge

Most of us, chemists or otherwise, have probably come across pH indicators at one point or another. I’d be surprised if there’s anyone out there who hasn’t, back in school, carried out the standard experiment of adding universal indicator to a variety of household liquids to identify them as acidic or alkaline. You might not be aware of the large range of different indicators that can be used to identify varying pHs, however, or the reasons behind the colour changes observed.

[…]

2103, 2014
  • Inorganic Paint Pigment Compounds

Inorganic Pigment Compounds – The Chemistry of Paint

March 21st, 2014|

Click to enlarge

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 future graphic).

[…]

503, 2014
  • Transition Metal Ion Colours Aqueous Complexes

Colours of Transition Metal Ions in Aqueous Solution

March 5th, 2014|

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 copper, is no longer the shiny, metallic orange of copper, but a pale green colour given by the compound copper carbonate.

[…]

602, 2014

Metal Ion Flame Test Colours Chart

February 6th, 2014|

Click to enlarge

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.

[…]