Practice chemistry entrance questions online

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


(1) Due to the presence of an unpaired electron, free radicals are:

(a) Chemically reactive
(b) Chemically inactive
(c) Anions
(d) Cations

Answer (a) Chemically reactive

(2) Lattice energy of an ionic compounds depends upon

(a) Charge on the ion only
(b) Size of the ion only
(c) Packing of ions only
(d) Charge on the ion and size of the ion

Answer (d) Charge on the ion and size of the ion

(3) The highest electrical conductivity of the following aqueous solutions is of

(a) 0.1 M acetic acid
(b) 0.1 M chloroacetic acid
(c) 0.1 M fluoroacetic acid
(d) 0.1 M difluoroacetic acid

Answer (d) 0.1 M difluoroacetic acid

(4) Which one of the following statements is NOT true about the effect of an increase in temperature on the distribution of molecular speeds in a gas?

(a) The most probable speed increases
(b) The fraction of the molecules with the most probable speed increases
(c) The distribution becomes broader
(d) The area under the distribution curve remains the same as under the lower temperature

Answer (b) The fraction of the molecules with the most probable speed increases

(5) Two solutions of a substance (non electrolyte) are mixed in the following manner. 480 ml of 1.5 M first solution + 520 mL of 1.2 M second solution. What is the molarity of the final mixture?

(a) 1.20 M
(b) 1.50 M
(c) 1.344 M
(d) 2.70 M

Answer (c) 1.344 M

(6) A reaction involving two different reactants can never be

(a) Unimolecular reaction
(b) First order reaction
(c) second order reaction
(d) Bimolecular reaction

Answer (a) Unimolecular reaction

(7) If we consider that 1/6 in place of 1/12 mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will

(a) Decrease twice
(b) Increase two fold
(c) Remain unchanged
(d) Be a function of the molecular mass of the substance

Answer (c) Remain unchanged

(8) In a multi – electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic acid and electric fields?
(1) n = 1, l = 0, m = 0
(2) n = 2, l = 0, m = 0
(3) n = 2, l = 1, m = 1
(4) n = 3, l = 2, m = 1
(5) n = 3, l = 2, m = 0

(a) (a) and (b)
(b) (b) and (c)
(c) (c) and (d)
(d) (d) and (e)

Answer (d) (d) and (e)

(9) During the process of electrolytic refining of copper, some metals present as impurity settle as ‘anode mud’ These are

(a) Sn and Ag
(b) Pb and Zn
(c) Ag and Au
(d) Fe and Ni

Answer (c) Ag and Au

(10) The disperse phase in colloidal iron (III) hydroxide and colloidal gold is positively and negatively charged, respectively, which of the following statements is NOT correct?

(a) magnesium chloride solution coagulates, the gold sol more readily than the iron
(III) hydroxide sol.
(b) sodium sulphate solution causes coagulation in both sols
(c) mixing the sols has no effect
(d) coagulation in both sols can be brought about by electrophoresis

Answer (c) mixing the sols has no effect