POST UTME BELLS UNIVERSITY 2025 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
The reaction 2NO(g) + O2(g) → 2NO2(g) has a rate cons\tant of 0.05 s^-1 at 298 K. If the initial concentrations of NO and O2 are 0.1 M and 0.05 M, respectively, calculate the concentration of NO2 after 10 minutes.
A. 0.05 M
B. 0.1 M
C. 0.15 M
D. 0.2 M
Question 2
The reaction of hydrogen gas with oxygen gas is represented by the equation: 2H2(g) + O2(g) → 2H2O(l). If 2.0 L of hydrogen gas is added to 1.0 L of oxygen gas, what is the limiting reac\tant?
A. H2(g)
B. O2(g)
C. H2O(l)
D. None of the above
Question 3
A diagram of a titration setup is shown below. What is the purpose of the burette?
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
Question 4
A solution contains 1.0 g of glu\cose (C6H12O6) per 100 mL of solution. What is the molarity of the solution?
A. 0.1 M
B. 0.5 M
C. 1.0 M
D. 2.0 M
Question 5
The half-life of a radioactive subs\tance is 10 years. If 100 g of the subs\tance is initially present, what is the amount of the subs\tance remaining after 20 years?
A. 50 g
B. 25 g
C. 12.5 g
D. 6.25 g
Question 6
A 1.0 M solution of NaOH is mixed with a 1.0 M solution of HCl. What is the pH of the resulting solution?
A. 1
B. 2
C. 3
D. 4
Question 7
A 25.0 mL sample of 0.100 M NaOH is mixed with 25.0 mL of 0.100 M HCl. What is the pH of the resulting solution?
A. 7.00
B. 7.50
C. 8.00
D. 9.00
Question 8
A 2.5 M solution of sodium hydroxide is prepared by dissolving 25 g of sodium hydroxide in 100 mL of water. What is the concentration of the solution in moles per liter?
A. 2.5 M
B. 5.0 M
C. 10.0 M
D. 12.5 M
Question 9
A 2.0 g sample of a subs\tance is burned in a bomb calorimeter. The heat released is 1000 J. What is the enthalpy change of the reaction?
A. -500 J/g
B. -1000 J/g
C. -1500 J/g
D. -2000 J/g
Question 10
A 2.5 g sample of a subs\tance is dissolved in 50 mL of water. If the resulting solution has a concentration of 0.25 M, what is the molar mass of the subs\tance?
A. 10 g/mol
B. 20 g/mol
C. 30 g/mol
D. 40 g/mol
Question 11
Determine the pH of a 0.1 M solution of HCl at 25°C, given that the dissociation cons\tant of HCl is 10^\( -7 \).
A. 1
B. 2
C. 3
D. 4
Question 12
The reaction between sodium hydroxide (NaOH) and hydrochloric acid (HCl) is as follows: NaOH + HCl → NaCl + H2O. If 100 mL of 0.5 M NaOH is mixed with 100 mL of 0.5 M HCl, what is the pH of the resulting solution?
A. 7
B. 8
C. 9
D. 10
Question 13
A solution of H2SO4 is added to a solution of BaCl2. If the initial concentration of H2SO4 is 0.5 M and the initial concentration of BaCl2 is 0.2 M, what is the pH of the resulting solution after the reaction is complete?
A. 1
B. 2
C. 3
D. 4
Question 14
A 1.0 M solution of AgNO3 is mixed with a 1.0 M solution of NaCl. If the reaction is allowed to go to completion, what is the concentration of AgCl that will precipitate out of the solution?
A. 0.5 M
B. 1.0 M
C. 1.5 M
D. 2.0 M
Question 15
A 1.0 M solution of sodium carbonate is prepared by dissolving 10 g of sodium carbonate in 100 mL of water. What is the concentration of the solution in moles per liter?
A. 1.0 M
B. 2.0 M
C. 3.0 M
D. 4.0 M

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: