Chemistry MCQ Test Questions

1.	The enthalpy of vaporization of benzene is +35.3 kJ/mol at its boiling point of 80°C. The entropy change in the transition of vapour to liquid at its boiling point is ______. [in J mol–1 K–1] (A) +100 (B) –100 (C) –342 (D) +342	Answer: (B)
2.	The formation of [PtF6]- is the basis for the formation of Xenon fluorides. This is because (A) O2 and Xe have comparable sizes (B) both O2 and Xe are gases (C) O2 and Xe have comparable ionisation energies (D) O2 and Xe have comparable electronegativities	Answer: (C)
3.	The formula mass of Mohr's salt is 392. The iron present in it is oxidised by KMnO4 in acid medium. The equivalent mass of Mohr's salt is (A) 392 (B) 31.6 (C) 278 (D) 156	Answer: (A)
4.	The geometry of electron pairs around I in IF5 is (A) Octahedral (B) Trigonal bipyramidal (C) Square pyramidal (D) Pentagonal planar	Answer: (A)
5.	The half life time of 2g sample of radioactive nuclide 'X' is 15 min. The half life time of 1g sample of X is (A) 7.5 min (B) 15 min (C) 22.5 min (D) 30 min	Answer: (B)
6.	The highest magnetic moment is shown by the transition metal ion with the configuration (A) 3d2 (B) 3d5 (C) 3d7 (D) 3d9	Answer: (B)
7.	The IUPAC name of is (A) but-1-enoic acid (B) but-3-enoic acid (C) prop-2-enoic acid (D) pent-4-enoic acid	Answer: (B)
8.	The IUPAC name of the complex [Co (NH3)4Cl2] Cl is (A) tetraammine dichloro cobalt (III) chloride (B) dichloro tetraammine cobalt (III) chloride (C) tetraammine dichloro cobalt (IV) chloride (D) tetraammine dichloro cobalt (II) chloride	Answer: (A)
9.	The mass of glucose that should be dissolved in 50 g of water in order to produce the same lowering of vapour pressure as is produced by dissolving 1 g of urea in the same quantity of water is (A) 1 g (B) 3 g (C) 6 g (D) 18 g	Answer: (B)
10.	The maximum number of possible isomers in 1-bromo-2-methyl cyclobutane is (A) 2 (B) 4 (C) 16 (D) 8	Answer: (B)
11.	The pH of 10-8 M HCI solution is (A) 8 (B) more than 8 (C) between 6 and 7 (D) slightly more than 7	Answer: (C)
12.	The radii of Na+ and Cl- ions are 95 pm and 181 pm respectively. The edge length of NaCl unit cell is (A) 276 pm (B) 138 pm (C) 552 pm (D) 415 pm	Answer: (C)
13.	The reaction C2H5ONa + C2H5I ® C2H5OC2H5 + NaI is known as (A) Kolbe's synthesis (B) Wurtz's synthesis (C) Williamson's synthesis (D) Grignard's synthesis	Answer: (C)
14.	The rms velocity of hydrogen is  times the rms velocity of nitrogen. If T is the temperature of the gas, which of the following is true? (A)  =   (B) (C) (D)	Answer: (D)
15.	The solubility of Ca3(PO4)2 in water is y moles / litre. Its solubility product is (A) 6y4 (B) 36y4 (C) 64y5 (D) 108y5	Answer: (D)