Question

Metals are generally hard. Which of the following metals is an exception and can be cut with a knife?

• A. Iron
• B. Sodium
• C. Gold
• D. Magnesium

Answer 1

The correct option is B

Sodium

Explanation of correct answer:

Option B Sodium

• All metals are hard except Lithium, Potassium, and Sodium which are soft and can be cut with a knife.
• Sodium is the second least dense metal after Lithium.
• It is a silvery-white metal with a waxy appearance.
• They have bright and shiny surfaces on the first cut but it quickly becomes dull as Sodium reacts with Oxygen in the air.
• Since Sodium is very reactive, it can be stored in kerosene.

Explanation of incorrect answer:

Option A Iron

• Iron is a hard and dense metal that is malleable and ductile.
• Therefore, it can't be cut with a knife.
• Hence option A is incorrect

Option C Gold

• Gold is a hard and dense metal that is malleable and ductile.
• Therefore, it can't be cut with a knife.
• Hence option C is incorrect

Option D Magnesium

• Magnesium is a hard and dense metal that is malleable and ductile.
• Therefore, it can't be cut with a knife.
• Hence option D is incorrect