Question

……… is the only metal which is brittle and crumbles into powder.

• A. Sodium
• B. Zinc
• C. Calcium
• D. Potassium

Answer 1

The correct option is B

Zinc

The explanation of the Correct option:

Option B, Zinc Zn

• Brittleness is the polar opposite of ductility, in which a material breaks when tensile force is applied to stretch it.
• Zinc is more brittle than other metals.

The explanation for incorrect options:

Option A, Sodium Na

• Sodium is metal instead of hard, it is soft in nature and easily cut with a knife.
• It is kept in kerosene oil as it highly reacts with water and air.

Option C, Calcium Ca

• Although pure calcium is a beautiful, silvery-white metal.
• It quickly becomes covered in an oxide layer when exposed to normal air conditions.
• The metal is malleable and soft.

D, Potassium K

• Potassium is also soft in nature instead of hard nature.
• It is also kept in kerosene because it is highly reactive with air.

Thus Option B, Zinc is the correct option.