UTME Chemistry 1986 JAMB Past Questions and Answers, Jamb, Pre-degree, Nursing, Waec, Neco

UTME Chemistry 1986 JAMB Past Questions and Answers

1. Which of the following solutions will conduct the least amount of electricity?

Options

A) 2.00 M aqueous solution of NaOH

B) 0.01 M aqueous solution of NaOH

C) 0.01 M aqueous solution of hexanoic acid

D) 0.01 M aqueous solution of sugar

The correct answer is D.

2. How many coulombs of electricity are passed through a solution in which 6.5 amperes are allowed to run for 1.0 hour?

Options

A) 3.90 x 102 coulombs

B) 5.50 x 103 coulombs

C) 6.54 x 103 coulombs

D) 2.34 x 104 coulombs

The correct answer is D.

3. Which of these represents a redox reaction?

Options

A) AgNO3 + NaCl → AgCAl + NaNO3

B) H2S + Pb(NO3) → PbS + 2HNO3

C) CaCO3 → CaO + CO2

D) Zn + 2HCl → ZnCl2 + H2

The correct answer is D.

4. 20 cm3 of 1.0 molar NH4OH solution when neutralized with 20.05cm3 of 0.1 molar HCl liberated -102 joules of heat. Calculate the heat of neutralization of NH4OH?

Options

A) -51.O KJ mol-

B) +57.3 KJ mol-

C) +57.O KJ mol-

D) +51.0 KJ mol-

The correct answer is A.

Explanation:

NH4OH = 20cm of 0.1 m

NH4 + HCl → NH4Cl = H2O

Heat of Neutralization of NH4OH

= −1022−1022 = -51.0 KJ mole-1

5. Which of the following salts when dissolved in water will NOT give the corresponding pH value?

Options

A) NaHSO4, pH < 5

B) Na2CO3, pH > 8

C) Na2Cl,pH = 7

D) NaHCO, pH < 6

The correct answer is D.