Magnesium is element number 12 in our International Year of the Periodic Table elements series. It’s a key component of the pigment that plants use to photosynthesis, and also finds use in sparklers and fireworks.

A single magnesium ion is bound at the centre of chlorophyll, the pigment that plants use to harvest energy from sunlight. Chlorophyll gives plants their green colour; if they cannot get enough magnesium from the soil, their leaves start to yellow.

Another use of magnesium related to light is in fireworks, sparklers, and flares. Strips of magnesium burn with a searingly bright white light, a demonstration many of us will remember from school chemistry lessons. Powdered magnesium in sparklers and fireworks, combined with oxidising chemicals, reproduces this effect on a larger scale.

Magnesium sulfate, or Epsom salt, was traditionally used as a component of bath salts, minerals added to bathwater. Athletes use it to soothe sore muscles, and gardeners can add it to soil to increase the amount of magnesium available to plants. Magnesium sulfate also finds common use in chemical synthesis, where it’s used as a solid to remove residual water from reaction products.

Remember, you can keep track of all of the previous entries in this series on the site here, or on the Royal Society of Chemistry’s dedicated page.