1.

Brass gets discoloured in air because of the presence of which of the following gases in air?

A. Oxygen B. Hydrogen sulphide
C. Carbon dioxide D. Nitrogen
Answer:B
Explanation: No answer description available for this question.

2.

Which of the following is a non metal that remains liquid at room temperature?

A. Phosphorous B. Bromine
C. Chlorine D. Helium
Answer:B
Explanation: No answer description available for this question.

3.

Chlorophyll is a naturally occurring chelate compound in which central metal is

A. copper B. magnesium
C. iron D. calcium
Answer:B
Explanation: No answer description available for this question.

4.

Which of the following is used in pencils?

A. Graphite B. Silicon
C. Charcoal D. Phosphorous
Answer:A
Explanation: No answer description available for this question.

5.

Which of the following metals forms an amalgam with other metals?

A. Tin B. Mercury
C. Lead D. Zinc
Answer:B
Explanation: No answer description available for this question.