POST UTME OSUSTECH 2024 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
Calculate the molar mass of a compound with the empirical formula C3H6O.
A. 60 g/mol
B. 90 g/mol
C. 120 g/mol
D. 180 g/mol
Question 2
A 0.1 M solution of NaOH is prepared by dissolving 0.1 mol of NaOH in 1 L of water. Calculate the concentration of the solution in g/L.
A. 2 g/L
B. 4 g/L
C. 6 g/L
D. 8 g/L
Question 3
A diagram of a titration setup is shown below. If 25.0 mL of 0.100 M $\text{NaOH}$ is required to neutralize 20.0 mL of a weak acid, what is the concentration of the acid?
A. 0.0500 M
B. 0.100 M
C. 0.200 M
D. 0.500 M
Question 4
A 0.1 M solution of NaCl is prepared by dissolving 6.0 g of NaCl in 100 mL of water. What is the concentration of Cl^- ions in the solution?
A. 0.1 M
B. 0.05 M
C. 0.01 M
D. 0.005 M
Question 5
A 0.1 M solution of NaOH is prepared by dissolving 0.1 mol of NaOH in 1 L of water. Calculate the concentration of the solution in g/L.
A. 2 g/L
B. 4 g/L
C. 6 g/L
D. 8 g/L
Question 6
The element with atomic number 12 is _______.
A. Mg
B. Ca
C. Sr
D. Ba
Question 7
A sample of CO2 gas occupies a volume of 2.5 L at a pressure of 1.5 atm. What is the volume of the gas at a pressure of 3.0 atm?
A. 1.0 L
B. 2.0 L
C. 3.0 L
D. 4.0 L
Question 8
A 0.500 M solution of NaCl is electrolyzed u\sing a platinum electrode. If the cell potential is 2.71 V, what is the mass of Cl2(g) produced at the anode in 2.00 hours?
A. 0.250 g
B. 0.500 g
C. 1.00 g
D. 2.00 g
Question 9
A 2.0 M solution of HCl is mixed with a 1.0 M solution of NaOH. What is the pH of the resulting solution?
A. 1.0
B. 2.0
C. 3.0
D. 4.0
Question 10
A 0.1 M solution of a weak acid HA is titrated with 0.1 M NaOH. If the initial pH of the acid solution is 3.5, what is the pH of the solution after the addition of 20 mL of 0.1 M NaOH?
A. 4.5
B. 5.5
C. 6.5
D. 7.5
Question 11
A 25.0 mL sample of 0.100 M NaOH is titrated with 0.100 M HCl. What is the pH of the solution after the titration?
A. 7.00
B. 8.00
C. 9.00
D. 10.00
Question 12
A 10.0 g sample of a compound is dissolved in 100.0 mL of water. What is the molarity of the solution?
A. 0.1 M
B. 0.5 M
C. 1.0 M
D. 5.0 M
Question 13
Determine the s\tandard enthalpy of formation of ΔHₓSOₓ(ₓl) from the following data: ΔHₓf(ΔHₓO(ₓl)) = -285.8 kJ/mol, ΔHₓf(ₓS(ₓl)) = 0 kJ/mol, ΔHₓf(ₓHₓ(ₓl)) = 0 kJ/mol.
A. -296.8 kJ/mol
B. -286.8 kJ/mol
C. -286.8 kJ/mol
D. -296.8 kJ/mol
Question 14
The following reaction occurs at 298 K: 2CH4(g) + 3O2(g) → 2CO2(g) + 4H2O(l). If ΔH = -2210 kJ/mol, what is the s\tandard enthalpy of formation of O2(g)?
A. 0 kJ/mol
B. 0 kJ/mol + 393.5 kJ/mol
C. 0 kJ/mol + 393.5 kJ/mol + 2\( 0 kJ/mol \)
D. 0 kJ/mol + 393.5 kJ/mol + 2\( 0 kJ/mol \) + 2\( 0 kJ/mol \)
Question 15
A metal alloy contains 80% copper and 20% zinc. If 500g of the alloy is melted and cast into a new shape, what is the mass of copper in the new shape?
A. 400g
B. 450g
C. 500g
D. 550g

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: