Which metal is added to steel to make it resistant to rust?

Correct option is A

Correct Answer: A. Chromium

• Chromium is the key element added to steel to form stainless steel.

• It forms a thin, invisible layer of chromium oxide on the surface, which prevents further oxidation (rusting).

• To be classified as stainless steel, the steel must contain at least 10.5% chromium.

• Aluminium: Used in light-weight alloys, not for rust resistance in steel.

• Carbon: Present in steel to increase hardness and strength, but does not prevent rust.

• Copper: Slightly improves corrosion resistance, but not effective alone in making steel rust-resistant.

• Stainless steel is widely used in:

  • Cutlery and kitchenware

  • Medical instruments

  • Construction and architecture

  • Automotive and aerospace parts