Multiple choice general knowledge science & technology K Kelium Potassium Phosphorus Krypton Reveal answer Fill a bubble to check yourself B Correct answer Explanation K is the symbol for potassium, derived from its Latin name 'kalium'. This is why potassium uses K instead of Po. 'Kelium' and 'Krypton' (Kr) are incorrect - krypton is a different noble gas. Potassium is an essential alkali metal.