POST UTME AFE BABALOLA UNIVERSITY 2025 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A polymer is formed by the condensation reaction between a diol and a diacid. If the molecular weight of the diol is 180 g/mol and the molecular weight of the diacid is 150 g/mol, what is the molecular weight of the polymer formed?
A. 225 g/mol
B. 250 g/mol
C. 275 g/mol
D. 300 g/mol
Question 2
A 1.0 L sample of a gas at 2.0 atm and 25°C is compressed to 4.0 atm and 50°C. What is the new volume of the gas?
A. 0.25 L
B. 0.5 L
C. 1.0 L
D. 2.0 L
Question 3
The half-life of a radioactive subs\tance is 10 years. If a sample of this subs\tance has an initial activity of 100 Bq, what is its activity after 20 years?
A. 50 Bq
B. 25 Bq
C. 12.5 Bq
D. 6.25 Bq
Question 4
A gas at 300 K has a pressure of 2 atm. If the temperature is increased to 400 K, what is the new pressure?
A. 2.5 atm
B. 3.0 atm
C. 3.5 atm
D. 4.0 atm
Question 5
A 2.5-g sample of a metal carbonate is heated to produce a metal oxide and carbon dioxide gas. If the mass of the metal oxide produced is 2.1 g, calculate the percentage yield of the metal oxide.
A. 80%
B. 85%
C. 90%
D. 95%
Question 6
The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. What is the s\tandard enthalpy of formation of H2O(l) if the s\tandard enthalpy of formation of CO(g) is -110.5 kJ/mol and the s\tandard enthalpy of formation of H2(g) is 0 kJ/mol?
A. -285.8 kJ/mol
B. -241.8 kJ/mol
C. -393.5 kJ/mol
D. -110.5 kJ/mol
Question 7
A diagram of a simple black and white chemistry apparatus showing a titration setup is shown below. If 25 mL of 0.1 M HCl is added to 25 mL of 0.1 M NaOH, what is the pH of the resulting solution?
A. 7
B. 9
C. 11
D. 13
Question 8
A solution of hydrochloric acid is prepared by dissolving 10 g of hydrochloric acid in 100 mL of water. What is the concentration of the solution in terms of molarity?
A. 0.05 M
B. 0.1 M
C. 0.2 M
D. 0.5 M
Question 9
A solution of sodium hydroxide (NaOH) is titrated with a solution of hydrochloric acid (HCl). If 25.0 cm³ of the HCl solution is required to neutralize 20.0 cm³ of the NaOH solution, calculate the concentration of the HCl solution.
A. 0.1 M
B. 0.2 M
C. 0.3 M
D. 0.4 M
Question 10
The solubility of a subs\tance is defined as the maximum amount of the subs\tance that can dissolve in a given amount of solvent at a particular temperature. What is the term for the minimum amount of a subs\tance required to saturate a given amount of solvent?
A. Solubility limit
B. Saturated solution
C. Solubility product cons\tant
D. Solubility equilibrium cons\tant
Question 11
A 1.0 M solution of NaOH is titrated with a 1.0 M solution of HCl. Calculate the pH of the solution at the equivalence point.
A. 7
B. 8
C. 9
D. 10
Question 12
A gas at 300 K has a pressure of 2 atm. If the temperature is increased to 400 K, what is the new pressure?
A. 2.5 atm
B. 3.0 atm
C. 3.5 atm
D. 4.0 atm
Question 13
A metal X reacts with chlorine gas to form a white solid. The solid is soluble in water and conducts electricity. What is the identity of the metal X?
A. Na
B. K
C. Ca
D. Mg
Question 14
The reaction of nitrogen dioxide with water produces nitric acid and nitric oxide. Write the balanced chemical equation for this reaction, including the state of each subs\tance.
A. 4NO2 + 2H2O → 4HNO3 + O2
B. 4NO2 + 2H2O → 4HNO3 + 2NO
C. 4NO2 + 2H2O → 4HNO3 + 2O2
D. 4NO2 + 2H2O → 4HNO3 + 4NO
Question 15
A gas is collected over water at a temperature of 25°C and a pressure of 1 atm. If the vapor pressure of water at 25°C is 23.8 mmHg, what is the partial pressure of the gas?
A. 0.96875 atm
B. 0.975 atm
C. 0.9875 atm
D. 0.9925 atm

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Help others prepare! Share this practice hub: