Question

A metal reacts with oxygen to form a compound with high melting point. This compound is soluble in water. Which of the following elements can it be?

• A. Silicon
• B. Carbon
• C. Calcium
• D. Iron

Hint:

Calcium oxide is basic in nature and forms calcium hydroxide when dissolved in water. This is a common property of alkaline earth metal oxides.

Answer 1

The Correct Option is C

Calcium reacts with oxygen to form calcium oxide, \( \text{CaO} \), which has a high melting point and is soluble in water. This compound reacts with water to form calcium hydroxide.