POST UTME CHRISTOPHER UNIVERSITY 2024 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A 10.0 mL sample of a 0.100 M solution of potassium permanganate (KMnO4) is added to a 20.0 mL sample of a 0.100 M solution of sodium oxalate (Na2C2O4). Determine the number of moles of potassium permanganate (KMnO4) that react with sodium oxalate (Na2C2O4) according to the balanced equation: 2KMnO4 + 5Na2C2O4 + 3H2O → K2Cr2O7 + 2MnO2 + 10NaOH + 8CO2.
A. 0.0500 moles
B. 0.100 moles
C. 0.150 moles
D. 0.200 moles
Question 2
A 2 M solution of HCl is mixed with a 2 M solution of NaOH. What is the pH of the resulting solution?
A. 0
B. 1
C. 2
D. 7
Question 3
A sample of a metal oxide, M2O3, has a molar mass of 228 g/mol. If 2.50 g of the oxide is dissolved in water to form a solution, what is the concentration of the metal ion, M, in the solution?
A. 0.100 M
B. 0.200 M
C. 0.500 M
D. 1.00 M
Question 4
A sample of a gas at 25°C and 1 atm is compressed to 4 atm at cons\tant temperature. What is the new volume of the gas?
A. 0.25 L
B. 0.5 L
C. 1 L
D. 2 L
Question 5
A 0.1 M solution of a weak acid is titrated with 0.1 M NaOH. If 20 mL of NaOH is required to reach the equivalence point, what is the pH of the resulting solution?
A. 1
B. 2
C. 3
D. 7
Question 6
A 1.0 M solution of a strong acid HA is titrated with 1.0 M NaOH. If 10 mL of NaOH is required to reach the equivalence point, what is the initial concentration of HA?
A. 0.5 M
B. 1.0 M
C. 2.0 M
D. 5.0 M
Question 7
A 1.0 L container is filled with a mixture of 0.5 mol of an unknown gas and 0.2 mol of oxygen gas at 25°C. If the total pressure of the mixture is 1.5 atm, what is the mole \fraction of the unknown gas?
A. 0.4
B. 0.5
C. 0.6
D. 0.7
Question 8
The atomic radius of an element in Group 1 of the Periodic Table is 250 pm. If the element is in its +1 oxidation state, what is the radius of its ion?
A. 250 pm
B. 200 pm
C. 150 pm
D. 100 pm
Question 9
A 2.0 L flask contains 0.5 mol of a gas at a temperature of 298 K. If the gas is allowed to expand to a volume of 4.0 L at cons\tant temperature, what is the new pressure of the gas?
A. ( 0.125 atm )
B. ( 0.25 atm )
C. ( 0.5 atm )
D. ( 1.0 atm )
Question 10
A 0.1 M solution of a monoprotic acid is titrated with 0.1 M NaOH. If 25 mL of NaOH is required to reach the equivalence point, what is the number of moles of acid present in 100 mL of the acid solution?
A. 0.0025 mol
B. 0.005 mol
C. 0.0075 mol
D. 0.01 mol
Question 11
A 1.0 L container is filled with a mixture of 0.5 mol of an unknown gas and 0.2 mol of oxygen gas at 25°C. If the total pressure of the mixture is 1.5 atm, what is the mole \fraction of the unknown gas?
A. 0.4
B. 0.5
C. 0.6
D. 0.7
Question 12
A 25.0 mL sample of a 0.100 M solution of sodium hydroxide (NaOH) is titrated with a 0.100 M solution of hydrochloric acid (HCl). Determine the pH of the resulting solution after the titration is complete.
A. 1.00
B. 2.00
C. 3.00
D. 4.00
Question 13
A sample of a non-metallic oxide, X2O3, has a mass of 25.0 g. If the molar mass of X2O3 is 224 g/mol, what is the number of moles of X2O3 present in the sample?
A. ( 0.11 mol )
B. ( 0.12 mol )
C. ( 0.13 mol )
D. ( 0.14 mol )
Question 14
A mixture of 0.5 mol of an unknown gas and 0.2 mol of oxygen gas is placed in a 1 L container at 25°C. If the total pressure of the mixture is 1.5 atm, what is the partial pressure of the unknown gas?
A. 0.8 atm
B. 1.0 atm
C. 1.2 atm
D. 1.5 atm
Question 15
A 2.5 M solution of HCl is prepared by dissolving 25 g of HCl in water to make 1 L of solution. What is the molarity of the solution?
A. 2.5 M
B. 2.0 M
C. 1.5 M
D. 1.0 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: