POST UTME EKSU 2019 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 (k) of 2.50 × 10^\( -3 \) s^\( -1 \) at 298 K. What is the activation energy (Ea) for the reaction?
A. 50.0 kJ/mol
B. 60.0 kJ/mol
C. 70.0 kJ/mol
D. 80.0 kJ/mol
Question 2
A 1.0 M solution of sulfuric acid (H2SO4) is titrated with a 1.0 M solution of sodium hydroxide (NaOH). Calculate the pH of the solution at the equivalence point.
A. 7.0
B. 8.0
C. 9.0
D. 10.0
Question 3
A 2.5 M solution of sodium hydroxide (NaOH) is titrated with a 1.0 M solution of hydrochloric acid (HCl). Calculate the volume of HCl required to reach the equivalence point.
A. 250 mL
B. 500 mL
C. 750 mL
D. 1000 mL
Question 4
A sample of phosphorus (P4) has a mass of 25.0 g. Calculate the number of moles of P4 present.
A. 0.5 mol
B. 1.0 mol
C. 1.5 mol
D. 2.0 mol
Question 5
A diagram of a gas law setup is shown below. What is the relationship between the variables?
A. P1V1 = P2V2
B. P1V1 = T2V2
C. P1V1 = n2V2
D. P1V1 = m2V2
Question 6
A 1.00 M solution of HCl is prepared by dissolving 37.0 g of HCl in 1.00 L of water. What is the concentration of H+ ions in the solution?
A. 0.500 M
B. 0.750 M
C. 1.00 M
D. 1.25 M
Question 7
A 2-methylpropane molecule has a molecular formula of C_3H_8. What is the IUPAC name of this molecule?
A. 2-methylpropane
B. 2-methylbu\tane
C. 2-methylpen\tane
D. 2-methylhexane
Question 8
Determine the s\tandard Gibbs free energy change (ΔG°) for the reaction: 2NO(g) + O2(g) → 2NO2(g), given that ΔH° = -114.1 kJ/mol and ΔS° = -146.3 J/mol·K.
A. -114.1 kJ/mol
B. -146.3 kJ/mol
C. -114.1 kJ/mol - 146.3 J/mol·K
D. -114.1 kJ/mol + 146.3 J/mol·K
Question 9
A solution of sodium hydroxide (NaOH) is titrated with a solution of hydrochloric acid (HCl). If 25 cm^3 of 0.1 M HCl is required to neutralize 20 cm^3 of 0.2 M NaOH, calculate the concentration of the HCl solution.
A. 0.05 M
B. 0.1 M
C. 0.15 M
D. 0.2 M
Question 10
Determine the pH of a 0.1 M solution of HCl.
A. 1
B. 2
C. 3
D. 4
Question 11
The pH of a solution is 3.5. Calculate the concentration of hydrogen ions \( H+ \) in the solution.
A. 1.0 x 10^-4 M
B. 1.0 x 10^-3 M
C. 1.0 x 10^-2 M
D. 1.0 x 10^-1 M
Question 12
A 2.00 L flask contains 0.200 mol of an ideal gas at a temperature of 298 K. If the gas is compressed to half its original volume, calculate the new pressure of the gas in the flask.
A. 1.00 atm
B. 1.50 atm
C. 2.00 atm
D. 2.50 atm
Question 13
A sample of nitrogen gas (N2) occupies a volume of 2.5 L at a pressure of 1.5 atm and a temperature of 298 K. Calculate the number of moles of N2 present.
A. 0.15 mol
B. 0.25 mol
C. 0.35 mol
D. 0.45 mol
Question 14
A solution of 0.1 M HCl is titrated with 0.1 M NaOH. If 50 mL of the HCl solution is titrated with 25 mL of the NaOH solution, what is the pH of the resulting solution?
A. 1
B. 2
C. 3
D. 4
Question 15
The boiling point of a solution containing 10.0 g of glu\cose (C6H12O6) in 100.0 g of water is 102.5°C. Calculate the molality of the solution.
A. 0.500 m
B. 1.00 m
C. 1.50 m
D. 2.00 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: