Solved Question Paper of Combined Recruitment Test (Computer Based Recruitment Test) conducted by UPSC for the Posts of Foreman (Chemical)/ Assistant Engineer (NQA) (Chemical Engineering)/ Senior Scientific Officer Grade-II (Chemical)/ Additional Assistant Director (Safety) (Chemical)/ Senior Scientific Assistant (Chemical)/ Junior Works Manager (Chemical) in the Ministry of Defence held on 16.07.2017.

1. Which one of the following is an example of amphoteric oxide?

Answer: (d)

2. Which one of the following material is used for control rods in Uranium reactors?
(a) Boron Steel
(b) Antimony
(c) Carbon Steel
(d) Titanium

Answer: (a)

3. What is the frequency of the radiation with a wavelength of 10.6 𝜇m, produced by 𝐶𝑂2(𝑔 ) laser?

Answer: (c)

4. What is the concentration of a solution of cane sugar (C12H22O11) which is isotonic with a solution containing 9.0 𝑔 of urea CO(NH2)2?
(a) 34.2 𝑔/𝑙
(b) 51.3 𝑔/𝑙
(c) 25.6 𝑔/𝑙
(d) 17.1 𝑔/𝑙

Answer: (b)

5. A hydrocarbon contains 86 % carbon, 448 ml of the hydrocarbon weighs 1.68 𝑔 of STP. Then the hydrocarbon is
(a) ALKENE
(b) ALKANE
(c) ALKYNE
(d) ARENE

Answer: (a)

6. When a solution of a metal salt is treated with ammonia solution, a white precipitate is formed which is insoluble in excess of ammonia. When same solution is treated with NaOH, a white precipitate is formed which dissolves in excess of NaOH. The cation is

Answer: (c)

7. What is the solubility product of lead iodide at 25°𝐶? Its solubility at that temperature is 0.7 𝑔/𝑙, atomic weight of Pb=207.2 and I=127.

Answer: (b)

8. The diameter measured under various trials for a wire using a microscope were 0.205 𝜇m, 0.209 𝜇m and 0.198 𝜇m. If the known diameter is  , the percentage of error for an average measurement is
(a) 1.8 %
(b) 3.5 %
(c) 2.4 %
(d) 2.0 %

Answer: (d)

9. Which one of following is the correct sequence in decreasing order of the dielectric constants?
(a) Sulfuric acid > water > ethanol > decane
(b) Water >sulfuric acid > ethanol > decane
(c) Water >sulfuric acid > decane > ethanol
(d) Sulfuric acid > ethanol > water > decane

Answer: (a)

10. Which one of the following is having isotonic nuclei?

Answer: (c)