POST UTME UNIPORT 2018 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A reaction is represented by the equation: 2A + B → 2C + D. If the rate of disappearance of A is 0.05 M/s and the rate of appearance of C is 0.02 M/s, what is the rate of appearance of D?
A. 0.01 M/s
B. 0.02 M/s
C. 0.03 M/s
D. 0.04 M/s
Question 2
A polymer has a molecular weight of 100,000 g/mol and a degree of polymerization of 500. What is the molar mass of the repeating unit?
A. 200 g/mol
B. 400 g/mol
C. 500 g/mol
D. 600 g/mol
Question 3
A 25.0 mL sample of 0.100 M HCl is titrated with 0.100 M NaOH. Calculate the pH of the solution after the addition of 25.0 mL of NaOH.
A. 2.00
B. 3.00
C. 4.00
D. 5.00
Question 4
The atomic radius of a certain element is 1.5 Å. If the element has an atomic number of 12, what is the expected value of the atomic radius of its isotope with mass number 25?
A. 1.2 Å
B. 1.5 Å
C. 1.8 Å
D. 2.0 Å
Question 5
The pH of a solution is given by the equation: pH = -\log[H+]. If the concentration of H+ ions in a solution is 1.0 x 10^-4 M, calculate the pH of the solution.
A. 3
B. 4
C. 5
D. 6
Question 6
In the context of environmental chemistry, what is the primary mechanism by which pollu\tants are transported from the atmosphere to the soil?
A. Dry deposition
B. Wet deposition
C. Runoff
D. Leaching
Question 7
The half-life of a radioactive subs\tance is 5 years. If the initial amount of the subs\tance is 100g, how much of the subs\tance will remain after 10 years?
A. 50g
B. 75g
C. 87.5g
D. 100g
Question 8
A sample of gas has a volume of 2.5 L at a pressure of 1.5 atm and a temperature of 300 K. What is the volume of the gas at a pressure of 3.0 atm and a temperature of 400 K?
A. 1.0 L
B. 2.0 L
C. 3.0 L
D. 4.0 L
Question 9
A solution of HCl is titrated with a solution of NaOH. The initial pH of the HCl solution is 2.0. What is the pH of the solution after the addition of 20 mL of 0.1 M NaOH?
A. 3.0
B. 4.0
C. 5.0
D. 6.0
Question 10
The reaction: 2H2(g) + O2(g) → 2H2O(l) has a s\tandard enthalpy change (ΔH°) of -572 kJ/mol. Calculate the s\tandard entropy change (ΔS°) for the reaction, given that the s\tandard entropy of H2(g) is 130.7 J/mol·K, the s\tandard entropy of O2(g) is 205.14 J/mol·K, and the s\tandard entropy of H2O(l) is 70.0 J/mol·K.
A. -220 J/mol·K
B. 220 J/mol·K
C. -420 J/mol·K
D. 420 J/mol·K
Question 11
A solution of 0.1M HCl is mixed with a solution of 0.1M NaOH. What is the pH of the resulting solution?
A. 1
B. 7
C. 9
D. 11
Question 12
A solution of 0.1 M HCl is electrolyzed u\sing a platinum electrode. If the cell potential is 2.0 V, what is the mass of hydrogen gas produced at the cathode in 2 hours?
A. 1.2 g
B. 1.5 g
C. 1.8 g
D. 2.0 g
Question 13
A 1.00 M solution of a weak acid HA is 10.0% dissociated at 25.0°C. What is the pH of the solution?
A. 2.00
B. 3.00
C. 4.00
D. 5.00
Question 14
The reaction between sodium hydroxide and hydrochloric acid is given by the equation: NaOH + HCl → NaCl + H2O. If 2.0 moles of NaOH react with excess HCl, calculate the number of moles of NaCl produced.
A. 1.0
B. 2.0
C. 3.0
D. 4.0
Question 15
A polymer has a molecular weight of 50,000 g/mol and a degree of polymerization of 500. Calculate the molar mass of the repeating unit.
A. 100 g/mol
B. 200 g/mol
C. 50 g/mol
D. 25 g/mol

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: