Question

A metal which is lighter than water is:

• A. lithium
• B. gold
• C. silver
• D. iron

Answer 1

The correct option is A lithium

Lithium has a density of (0.534 g/cm3) which is lower than water (1 g/cm${}^3$). Two other metallic elements are less dense than water. Potassium has a density of 0.862 g/cm${}^3$ while sodium has a density of 0.971 g/cm${}^3$. All of the other metals on the periodic table are denser than water. While lithium, potassium, and sodium are all light enough to float on water, they are also highly reactive.