POST UTME LAUTECH 2020 Chemistry | Objective

Are you preparing for POST UTME LAUTECH exams? Reviewing past questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2020 Chemistry (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1
In the electrolysis of water, what is the primary product at the cathode?
A. O2
Correct B. H2
C. OH-
D. H+

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 2
What is the major difference between primary and secondary alcohols?
A. Primary alcohols have a higher boiling point than secondary alcohols
B. Secondary alcohols are more soluble in water than primary alcohols
Correct C. Primary alcohols are more reactive than secondary alcohols
D. Secondary alcohols have a higher molecular weight than primary alcohols

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 3
A 2.5g sample of a subs\tance is found to have a mass of 3.2g after being heated in a crucible. What is the mass of the subs\tance that was lost during heating?
Correct A. 0.7g
B. 1.2g
C. 1.7g
D. 2.2g

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 4
A 5.0L container is filled with 2.0mol of an ideal gas at 25°C. What is the pressure of the gas?
A. 1.0atm
B. 1.5atm
Correct C. 2.0atm
D. 2.5atm

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 5
A 10.0g sample of a subs\tance is found to have a mass of 8.0g after being heated in a crucible. What is the mass of the subs\tance that was lost during heating?
A. 1.0g
B. 2.0g
C. 3.0g
Correct D. 4.0g

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 6
A sample of an ideal gas is heated at cons\tant volume. Which of the following statements is true about the change in the gas's properties?
A. The gas expands and its pressure increases.
B. The gas contracts and its pressure decreases.
Correct C. The gas expands and its pressure remains cons\tant.
D. The gas contracts and its pressure increases.

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 7
A solution of sodium chloride (NaCl) is prepared by dissolving 35.5 g of NaCl in 100 mL of water. What is the molar concentration of the solution?
A. 0.1 M
B. 0.5 M
Correct C. 1.0 M
D. 2.0 M

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 8
A diagram of a titration apparatus is shown below. What is the purpose of the burette in the apparatus?
Correct A. To measure the volume of the titrant.
B. To measure the volume of the analyte.
C. To mix the titrant and analyte.
D. To measure the pH of the solution.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 9
A sample of a non-metallic element is heated in a crucible. What is the expected change in the element's properties?
Correct A. The element sublimes and its color changes.
B. The element melts and its color remains the same.
C. The element sublimes and its color remains the same.
D. The element melts and its color changes.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 10
A diagram of a gas collection apparatus is shown below. What is the purpose of the gas collection tube in the apparatus?
Correct A. To collect the gas produced.
B. To measure the volume of the gas produced.
C. To mix the gas with another gas.
D. To measure the pH of the solution.

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 11
Determine the pH of a 0.1 M solution of HCl, 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 12
A 25 mL sample of 0.5 M NaOH is titrated with 0.5 M HCl. Calculate the volume of HCl required to reach the equivalence point.
A. 12.5 mL
B. 25 mL
Correct C. 37.5 mL
D. 50 mL

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 13
A solution contains 0.1 M HCl and 0.1 M NaOH. What is the pH of the 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 14
A 10 mL sample of 0.5 M HCl is titrated with 0.5 M NaOH. Calculate the pH of the solution after 5 mL of NaOH has been added.
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 15
A 20 mL sample of 0.2 M NaOH is titrated with 0.2 M HCl. Calculate the volume of HCl required to reach the equivalence point.
A. 10 mL
B. 20 mL
Correct C. 30 mL
D. 40 mL

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 16
Calculate the s\tandard enthalpy change for the combustion of 1 mole of propane (C3H8) at 298 K and 1 atm. The s\tandard enthalpy of formation of C3H8 is -103.8 kJ/mol, and the s\tandard enthalpy of formation of CO2 is -393.5 kJ/mol.
Correct A. -2220 kJ/mol
B. -1038 kJ/mol
C. 2220 kJ/mol
D. 1038 kJ/mol

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 17
A 0.5 M solution of NaOH is mixed with a 0.5 M solution of HCl. What is the pH of the resulting solution?
Correct A. 7
B. 9
C. 11
D. 13

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 18
A 2.0 g sample of a compound is dissolved in 50 mL of water. The resulting solution has a concentration of 0.1 M. What is the molar mass of the compound?
A. 20 g/mol
Correct B. 40 g/mol
C. 60 g/mol
D. 80 g/mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 19
A 1.0 M solution of HCl is mixed with a 1.0 M solution of NaOH. What is the resulting concentration of HCl after the reaction is complete?
Correct A. 0.5 M
B. 1.0 M
C. 1.5 M
D. 2.0 M

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 20
A 2.0 g sample of a compound is dissolved in 50 mL of water. The resulting solution has a concentration of 0.1 M. What is the molar mass of the compound?
A. 20 g/mol
Correct B. 40 g/mol
C. 60 g/mol
D. 80 g/mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 21
A 1.0 M solution of HCl is titrated with 0.5 M NaOH. If 25 mL of HCl is required to reach the equivalence point, what is the volume of NaOH required to reach the equivalence point?
A. 12.5 mL
B. 25 mL
Correct C. 37.5 mL
D. 50 mL

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 22
A sample of CO2 is collected over water at a temperature of 25°C and a pressure of 1 atm. If the partial pressure of CO2 is 0.75 atm, what is the mole \fraction of CO2 in the gas mixture?
A. 0.25
B. 0.5
Correct C. 0.75
D. 1.0

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 23
A 2.0 M solution of NaOH is titrated with 1.0 M HCl. If 20 mL of HCl is required to reach the equivalence point, what is the pH of the resulting 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 24
A sample of N2 gas is collected over water at a temperature of 25°C and a pressure of 1 atm. If the partial pressure of N2 is 0.75 atm, what is the mole \fraction of N2 in the gas mixture?
A. 0.25
B. 0.5
Correct C. 0.75
D. 1.0

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 25
A 1.0 M solution of H2SO4 is titrated with 0.5 M NaOH. If 30 mL of H2SO4 is required to reach the equivalence point, what is the volume of NaOH required to reach the equivalence point?
A. 15 mL
B. 30 mL
Correct C. 45 mL
D. 60 mL

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