Chemistry Questions for Entrance Test

Chemistry Objective Type Questions with Answers for the preparation of Engineering Entrance Test like AIEEE, IIT-JEE, CET etc.

(1) Toluene is nitrated and the resulting product is reduced with tin and hydrochloric acid. The product so obtained is diazotised and then heated with cuprous bromide. The reaction mixture so formed contains

(a) mixture of o− and p−bromotoluenes
(b) mixture of o− and p−dibromobenzenes
(c) mixture of o− and p−bromoanilines
(d) mixture of o− and m−bromotoluenes

Answer (a) mixture of o− and p−bromotoluenes

(2) Phenol, when it first reacts with concentrated sulphuric acid and then with concentrated nitric acid, gives

(a) 2,4,6-trinitrobenzene
(b) o-nitrophenol
(c) p-nitrophenol
(d) nitrobenzene

Answer (b) o-nitrophenol

(3) Larger number of oxidation states are exhibited by the actinoids than those by the lanthanoids, the main reason being

(a) 4f orbitals more diffused than the 5f orbitals
(b) lesser energy difference between 5f and 6d than between 4f and 5d orbitals
(c) more energy difference between 5f and 6d than between 4f and 5d orbitals
(d) more reactive nature of the actinoids than the lanthanoids

Answer (b) lesser energy difference between 5f and 6d than between 4f and 5d orbitals

(4) Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly?

(a) Metal sulphides are thermodynamically more stable than CS2
(b) CO2 is thermodynamically more stable than CS2
(c) Metal sulphides are less stable than the corresponding oxides
(d) CO2 is more volatile than CS2

Answer (a) Metal sulphides are thermodynamically more stable than CS2

(5) α-D-(+)-glucose and β-D-(+)-glucose are

(a) conformers
(b) epimers
(c) anomers
(d) enantiomers

Answer (c) anomers

(6) Which one of the following is the correct statement?

(a) Boric acid is a protonic acid
(b) Beryllium exhibits coordination number of six
(c) Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase
(d) B2H6.2NH3 is known as ‘inorganic benzene’

Answer (c) Chlorides of both beryllium and aluminium have bridged chloride structures in solid phase

(7) Among the following substituted silanes the one which will give rise to cross linked silicone polymer on hydrolysis is

(a) R4Si
(b) RSiCl3
(c) R2SiCl2
(d) R3SiCl

Answer (b) RSiCl3

(8) In a compound atoms of element Y from ccp lattice and those of element X occupy 2/3rd of tetrahedral voids. The formula of the compound will be

(a) X4Y3
(b) X2Y3
(c) X2Y
(d) X3Y4

Answer (a) X4Y3

(9) Amount of oxalic acid present in a solution can be determined by its titration with KMnO4 solution in the presence of H2SO4. The titration gives unsatisfactory result when carried out in the presence of HCl, because HCl

(a) gets oxidised by oxalic acid to chlorine
(b) furnishes H+ ions in addition to those from oxalic acid
(c) reduces permanganate to Mn2+
(d) oxidises oxalic acid to carbon dioxide and water

Answer (c) reduces permanganate to Mn2+

(10) Which one of the following pairs of species have the same bond order?

(a) CN− and NO+
(b) CN− and CN+
(c) O− and CN−
(d) NO+ and CN+

Answer (a) CN− and NO+