Definition

A soft, silvery-white metal that is liquid at room temperature and is very reactive. It is used in devices like photoelectric cells and has the atomic number 55.

Example

Cesium is used in atomic clocks because of its precise timekeeping abilities.

Conversation

Did you know that cesium is the most electropositive element?

Really? That's interesting! What’s it used for?

It's often found in photoelectric cells, apparently.

Wow, I had no idea it was so useful in technology!

Synonyms & Antonyms

Root Explanation

Cesium comes from the Latin word 'caesius' (meaning sky blue), which refers to the blue lines in its spectrum. The name reflects the element's distinctive spectral lines that appear blue when analyzed.

Memory Tip

Think of the Latin word 'caesius' meaning sky blue, which helps you remember that cesium is named for its blue spectral lines.

Visually Confused Words