Which one of the following metals floats in cold water?
Magnesium
Calcium
Potassium
Copper
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC NDA-2 – 2022
Metals less dense than water (density < 1 g/cm³) and which react with water tend to float. Potassium (density ~0.89 g/cm³) and Sodium (density ~0.97 g/cm³) are alkali metals that are less dense than water and react vigorously with cold water, producing hydrogen gas which aids flotation. Calcium (density ~1.55 g/cm³) is denser than water but reacts with cold water, and the hydrogen bubbles produced stick to its surface, causing it to float temporarily. Magnesium and Copper do not react with cold water in a way that causes them to float.