Chemistry mcq with answers

1.	In the conversion of X is (A) H2/Pt (B) Zn-Hg/HCl (C) Li/NH3 (D) NaBH4	Answer: (D)
2.	In the conversion of Br2 to , the oxidation number of Br changes from (A) zero to +5 (B) +1 to +5 (C) zero to -3 (D) +2 to +5	Answer: (A)
3.	In the following electron – dot structure, calculate the formal charge from left to right nitrogen atom; (A) –1, –1, +1 (B) –1, +1, –1 (C) +1, –1, –1 (D) +1, –1, +1	Answer: (B)
4.	In the following, the element with the highest ionisation energy is (A) [Ne]3s23p1 (B) [Ne]3s23p3 (C) [Ne]3s23p2 (D) [Ne]3s23p4	Answer: (B)
5.	In the reaction R - X the product B is (A) alkyl chloride (B) aldehyde (C) carboxylic acid (D) ketone	Answer: (C)
6.	In the reaction 2H2O2 ® 2H2O + O2 (A) Oxygen is oxidised only (B) Oxygen is reduced only (C) Oxygen is neither oxidised nor reduced (D) Oxygen is both oxidised and reduced	Answer: (D)
7.	In Tollen's test, aldehydes (A) Are oxidised to acids (B) Are reduced to alcohol (C) Neither reduced nor oxidised (D) Precipitate Ag+ as AgCI	Answer: (A)
8.	In which of the following complex ion, the central metal ion is in a state of sp3d2 hybridisation? (A) [CoF6]3- (B) [Co(NH3)6]3+ (C) [Fe(CN)6]3- (D) [Cr (NH3)6]3+	Answer: (A)
9.	In which one of the given formulae of xenon compounds there are five a-bonds and three p-bonds in it? (A) XeFO (B) XeF2O2 (C) XeF3O2 (D) XeF2O3	Answer: (D)
10.	Increasing order of carbon-carbon bond length for the following is C2H4        C2H2        C6H6        C2H6 (A)        (B)        (C)        (D) (A) C < B < A < D (B) B < C < A < D (C) D < C < A < B (D) B < A < C < D	Answer: (D)
11.	Inductive effect involves (A) displacement of s electrons (B) delocalisation of p  electrons (C) delocalisation of s  electrons (D) displacement of p  electrons	Answer: (A)
12.	Insulin regulates the metabolism of (A) minerals (B) amino acids (C) glucose (D) vitamins	Answer: (C)
13.	Liquor ammonia bottles are opened only after cooling. This is because (A) it is a mild explosive (B) it is a corrosive liquid (C) it is a lachrymatory (D) it generates high vapour pressure	Answer: (D)
14.	Lowest pKa is associated with	Answer: (C)
15.	Maximum efficiency of a commercial refrigerator which operates between –10° (inside temperature) and 25°C (outside temperature) is (A) 13.3% (B) 11.45% (C) 24.75% (D) 20%	Answer: (B)