Question

When calcium is immersed in water, it starts to .

• A. float
• B. sink
• C. disappear

Answer 1

The correct option is A float

Calcium reacts with water to form hydrogen gas. The bubbles of the hydrogen gas stick to the surface of the metal and makes it float. The reaction takes place as follows:
$\text{Ca(s)}+2{\text{H}}_2\text{O(l)}\to {\text{Ca(OH)}}_2\text{(aq)}+{\text{H}}_2\text{(g)}$