Element number 11 in our International Year of the Periodic Table series is sodium. Found in salt, and responsible for the traditional yellow glow of streetlights, sodium is also an important element for the normal function of our bodies.

The best-known sodium compound is sodium chloride or table salt. As well as seasoning your food, sodium chloride finds use in deicing. It’s the salt most responsible for the saltiness of seawater, and is also used in the production of many chemical products.

Sodium ions don’t just make your food taste good – they also play key roles in our bodies. They’re needed for your muscles and nerves to function, and also help regulate water levels in our bodies.

Sodium is also responsible for the yellow glow of traditional streetlights. These sodium-vapour lamps heat sodium metal until it becomes a gas, which gives off the characteristic yellow light. Increasingly, these streetlights are being replaced by LED lamps which consume less energy and reduce light pollution.

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.