2606, 2018
  • The colour of alexandrite

The chemistry of colour-changing alexandrite

June 26th, 2018|

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Decades of marketing have placed diamonds on a pedestal above other gemstones. They’re an engagement ring tradition and are also found in lots of other jewellery. However, there’s another, coloured gemstone which is arguably superior. Not content with being one colour, it can display a whole range of hues, depending on the light falling on it. The gemstone in question? Alexandrite.


1805, 2017
  • Making a Red Cabbage pH Indicator

Making a Red Cabbage pH Indicator: The Method and the Chemistry

May 18th, 2017|

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We all know examples of everyday substances that can be classified as acids or alkalis: lemon juice is acidic, bleach is alkaline, and so on. Another substance that can be found in your kitchen can be used to test other substances to determine whether they are acidic or alkaline. The chemicals that give red cabbage its colour also allow it to be used as a pH indicator – this post looks at how!


1004, 2017
  • C&EN – Easter Eggs Preview

The Chemistry of Dyeing Easter Eggs – in C&EN

April 10th, 2017|

Click to view full graphic on the C&EN site

With Easter just around the corner, this month’s edition of Periodic Graphics in C&EN takes a look at the chemistry behind the Easter tradition of dyeing eggshells different colours. Click to view the full graphic on the C&EN site!


1201, 2017
  • The Chemistry of Bodily Fluid Colours

The Chemistry of the Colours of Bodily Fluids

January 12th, 2017|

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A particular bodily fluid featured in the political news earlier this week, which got me thinking about the chemical causes behind the colours of the waste products we expel from our bodies. What makes urine golden, faeces brown, and bile green? The answers to all of these questions have a common chemical link.


1412, 2016
  • The Chemistry of LED lights and How LED lights work

A Basic Guide to How LED Lights Work

December 14th, 2016|

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Christmas isn’t far off now, and whether you’re celebrating it or not, you’ve may well have started seeing Christmas lights starting to appear adorning houses and Christmas trees. How do these lights actually work, and how can they be made to produce such an array of colours? This graphic takes a look at the chemistry.


1405, 2015
  • The Chemistry of Permanent Hair Dye Colours

The Chemistry of Permanent Hair Dyes

May 14th, 2015|

Today, hair dyes are widely used, either to cover up grey hairs, or simply by those wanting to change their natural hair colour. The chemistry behind how they change the colour of hair can actually get pretty complicated, but this graphic tries to boil it down to the key classes of chemicals involved, and an overview of the process that produces the dye molecules.