Friday, April 26, 2019

WBCS Polity and Constitution MCQs Prelims and Mains

WBCS Previous Years MCQs on General Science (Chemistry) P5

Chemistry - 05

21. Which of the following is a neutral oxide
(A) Calcium oxide
(B) Sulphur-di-Oxide
(C) Nitric oxide
(D) Zinc oxide.

Correct Answer: [D] Zinc oxide..
22. Which of the following mixtures can be separated by using separating funnel?
(A) Water + oil
(B) Petrol + kerosene
(C) Water + sugar
(D) Water + milk.

Correct Answer: [A] Water + oil.
23. Mg2+ is isoelectronic with
(A) Zn2+
(B) Cu+
(C) Ca2+
(D) Na+

Correct Answer: [D] Na+.
24. The half-life of a substance is 10 days. How much of the substance will be left after 40 days if the initial mass is 2 gm
(A) 0.0125 gm
(B) 1.25 gm
(C) 0.125 gm
(D) 5 gm.

Correct Answer: [C] 0.125 gm.
25. Brass is an alloy of
(A) Copper and Aluminium
(B) Copper and Zinc
(C) Iron and Copper
(D) Copper and Tin.

Correct Answer: [B] Copper and Zinc.


Post a Comment