POST UTME LASU 2025 Chemistry | Objective

Prepare for your exams with POST UTME LASU questions? Reviewing past/model questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2025 Chemistry (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1 View Details
Determine the pH of a 0.1 M solution of HCl in water at 25°C, given that the dissociation cons\tant of HCl is 10^\( -7 \).
A. 1
B. 2
C. 3
Correct D. 4

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 2 View Details
A diagram of a titration setup is shown below. If 25 mL of 0.1 M NaOH is added to 25 mL of 0.1 M HCl, what is the pH of the resulting solution?
A. 1
Correct B. 2
C. 3
D. 4

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 3 View Details
A 1.0 L solution contains 0.5 mol of a non-electrolyte solute. What is the mole \fraction of the solute?
Correct A. 0.5
B. 0.25
C. 0.75
D. 0.33

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 4 View Details
A diagram of a simple black and white chemistry apparatus showing a titration setup is shown below. If 25 mL of 0.1 M NaOH is added to 25 mL of 0.1 M HCl, what is the pH of the resulting solution?
A. 1
Correct B. 2
C. 3
D. 4

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 5 View Details
A 1.0 L solution contains 0.5 mol of a non-electrolyte solute. What is the mole \fraction of the solute?
Correct A. 0.5
B. 0.25
C. 0.75
D. 0.33

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 6 View Details
A reaction is said to be at equilibrium when the rates of forward and reverse reactions are equal. What is the name of the law that describes this condition?
Correct A. Le Chatelier's Principle
B. Gibbs Free Energy Equation
C. Equilibrium Cons\tant Expression
D. Rate Law

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 7 View Details
A solution of 0.1 M HCl is titrated with 0.1 M NaOH. What is the pH of the solution after 25 mL of NaOH has been added?
A. 1
B. 2
Correct C. 3
D. 4

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 8 View Details
A diagram of a titration setup is shown below.
A. The burette contains the acid.
B. The beaker contains the base.
Correct C. The burette contains the base.
D. The beaker contains the acid.

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 9 View Details
A reaction is said to be spon\taneous when the Gibbs Free Energy change is negative. What is the name of the equation that describes this condition?
Correct A. ΔG = ΔH - TΔS
B. ΔG = ΔH + TΔS
C. ΔG = -ΔH + TΔS
D. ΔG = ΔH - TΔS

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 10 View Details
A diagram of a chemical apparatus is shown below.
A. The test tube contains the acid.
B. The burette contains the base.
Correct C. The test tube contains the base.
D. The burette contains the acid.

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 11 View Details
The rate cons\tant (k) for a first-order reaction is given by the equation: k = Ae^\( -Ea/RT \). If the activation energy (Ea) is 100 kJ/mol, the gas cons\tant (R) is 8.314 J/mol*K, and the temperature (T) is 300 K, what is the value of the rate cons\tant (k) if the pre-exponential factor (A) is 1.0 x 10^10 s^-1?
A. 1.0 x 10^5 s^-1
B. 1.0 x 10^6 s^-1
C. 1.0 x 10^7 s^-1
Correct D. 1.0 x 10^8 s^-1

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 12 View Details
A solution of 0.1 M NaCl is prepared by dissolving 6.0 g of NaCl in 100 mL of water. What is the concentration of Na+ ions in the solution?
A. 0.01 M
B. 0.05 M
Correct C. 0.1 M
D. 0.5 M

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 13 View Details
A 2.0 L flask contains 1.0 atm of O2 at 25°C. What is the partial pressure of O2 in the flask?
A. 0.5 atm
Correct B. 1.0 atm
C. 1.5 atm
D. 2.0 atm

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 14 View Details
A sample of 1.0 g of C6H12O6 is burned in a bomb calorimeter. The heat of combustion is 13.8 kJ/g. What is the total heat of combustion for the sample?
A. 13.8 kJ
B. 27.6 kJ
C. 41.4 kJ
Correct D. 55.2 kJ

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 15 View Details
A solution of 0.1 M HCl is prepared by dissolving 6.0 g of HCl in 100 mL of water. What is the pH of the solution?
A. 1
B. 2
C. 3
Correct D. 4

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 16 View Details
A 2.0 L flask contains 1.0 atm of CO2 at 25°C. What is the partial pressure of CO2 in the flask?
A. 0.5 atm
Correct B. 1.0 atm
C. 1.5 atm
D. 2.0 atm

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 17 View Details
A sample of 1.0 g of C6H12O6 is burned in a bomb calorimeter. The heat of combustion is 13.8 kJ/g. What is the total heat of combustion for the sample?
A. 13.8 kJ
B. 27.6 kJ
C. 41.4 kJ
Correct D. 55.2 kJ

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 18 View Details
A solution of 0.1 M HCl is prepared by dissolving 6.0 g of HCl in 100 mL of water. What is the pH of the solution?
A. 1
B. 2
C. 3
Correct D. 4

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 19 View Details
A 2.0 L flask contains 1.0 atm of O2 at 25°C. What is the partial pressure of O2 in the flask?
A. 0.5 atm
B. 1.0 atm
C. 1.5 atm
D. 2.0 atm

Correct Answer: VIEW ANSWER

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 20 View Details
A sample of a metal oxide, M2O3, has a mass of 25.0 g and a volume of 2.50 cm3. If the density of the oxide is 4.50 g/cm3, calculate the molar mass of the oxide.
A. 150 g/mol
B. 200 g/mol
Correct C. 250 g/mol
D. 300 g/mol

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 21 View Details
A solution of HCl is prepared by dissolving 25.0 g of HCl in 100.0 cm3 of water. Calculate the concentration of the solution in mol/dm3.
Correct A. 0.25 mol/dm3
B. 0.50 mol/dm3
C. 1.00 mol/dm3
D. 2.00 mol/dm3

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 22 View Details
A 2.00 M solution of NaOH is prepared by dissolving 40.0 g of NaOH in 1000.0 cm3 of water. Calculate the concentration of the solution in mol/dm3.
A. 0.20 mol/dm3
Correct B. 0.40 mol/dm3
C. 0.80 mol/dm3
D. 1.60 mol/dm3

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 23 View Details
A sample of a gas has a volume of 2.50 dm3 at a pressure of 1.00 atm and a temperature of 20°C. Calculate the volume of the gas at a pressure of 2.00 atm and a temperature of 30°C.
A. 3.00 dm3
B. 4.00 dm3
Correct C. 5.00 dm3
D. 6.00 dm3

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 24 View Details
A 2.00 M solution of HCl is prepared by dissolving 40.0 g of HCl in 1000.0 cm3 of water. Calculate the concentration of the solution in mol/dm3.
A. 0.20 mol/dm3
Correct B. 0.40 mol/dm3
C. 0.80 mol/dm3
D. 1.60 mol/dm3

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 25 View Details
A sample of a metal oxide, M2O3, has a mass of 25.0 g and a volume of 2.50 cm3. If the density of the oxide is 4.50 g/cm3, calculate the molar mass of the oxide.
A. 150 g/mol
B. 200 g/mol
Correct C. 250 g/mol
D. 300 g/mol

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

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:
Chat with Support