Exam Body

Year

Subject

Paper Type

POST UTME RHEMA UNIVERSITY 2019 Chemistry | Objective

Are you preparing for POST UTME RHEMA UNIVERSITY exams? Reviewing past questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2019 Chemistry (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1

A reaction is said to be at equilibrium when the rates of forward and reverse reactions are equal. What is the name of the mathematical expression that describes the equilibrium cons\tant (Kc) in terms of the concentrations of reac\tants and products?

Correct A. The Law of Mass Action

B. The Law of Conservation of Energy

C. The Law of Equilibrium Cons\tant

D. The Law of Chemical Kinetics

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 2

A metal is said to be 'noble' if it does not readily react with other elements. Which of the following metals is an example of a noble metal?

A. Gold (Au)

Correct B. Silver (Ag)

C. Copper (Cu)

D. Zinc (Zn)

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 3

A hydrocarbon is a compound that contains only hydrogen and carbon atoms. What is the name of the type of hydrocarbon that has the general formula CnH2n+2?

Correct A. Alkane

B. Alkene

C. Alkyne

D. Aromatic Hydrocarbon

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 4

A reaction is said to be exothermic if it releases heat energy. What is the sign of the enthalpy change (ΔH) for an exothermic reaction?

A. +ve

Correct B. -ve

C. 0

D. ΔH is not related to heat energy

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 5

A metal is said to be 'malleable' if it can be pounded into thin sheets. Which of the following metals is an example of a malleable metal?

A. Gold (Au)

B. Silver (Ag)

Correct C. Copper (Cu)

D. Zinc (Zn)

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 6

Determine the s\tandard Gibbs free energy change for the reaction: 2Ag+(aq) + 2Cl-(aq) → 2AgCl(s) at 298 K and 1 atm, given that ΔH° = -127.5 kJ/mol and ΔS° = -173.5 J/mol·K.

A. -129.5 kJ/mol

Correct B. -127.5 kJ/mol

C. -125.5 kJ/mol

D. -123.5 kJ/mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 7

A 2.50 L sample of a gas at 298 K and 1.50 atm is compressed to 0.500 L at the same temperature. What is the new pressure of the gas?

A. 3.00 atm

B. 4.00 atm

Correct C. 5.00 atm

D. 6.00 atm

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 8

A 0.500 M solution of NaOH is mixed with a 0.500 M solution of HCl. What is the pH of the resulting solution?

A. 1.00

Correct B. 2.00

C. 3.00

D. 4.00

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 9

A 1.00 L sample of a 0.500 M solution of KNO3 is electrolyzed for 2.00 hours. What is the mass of oxygen gas collected at the anode?

A. 0.500 g

Correct B. 1.00 g

C. 1.50 g

D. 2.00 g

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 10

A 2.00 L sample of a 0.500 M solution of HCl is mixed with a 2.00 L sample of a 0.500 M solution of NaOH. What is the pH of the resulting solution?

A. 1.00

Correct B. 2.00

C. 3.00

D. 4.00

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 11

Determine the number of moles of $\text{O}_2$ required to react completely with 2.50 moles of $\text{C}_2\text{H}_4$ according to the equation $\text{C}_2\text{H}_4 + 3\text{O}_2 \rightarrow 2\text{CO}_2 + 2\text{H}_2\text{O}$.

A. 1.67 moles

B. 2.50 moles

Correct C. 3.75 moles

D. 5.00 moles

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 12

A 0.500 M solution of $\text{H}_2\text{SO}_4$ is mixed with 100. mL of 0.100 M $\text{Ba}$ \text{OH} $_2$. What is the concentration of the resulting solution?

A. 0.0500 M

Correct B. 0.100 M

C. 0.200 M

D. 0.500 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 13

The half-life of a certain radioactive subs\tance is 5.00 days. If 100. mg of the subs\tance is initially present, how much will remain after 20.0 days?

A. 10.0 mg

Correct B. 20.0 mg

C. 50.0 mg

D. 100 mg

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 14

A 2.00 M solution of $\text{HCl}$ is mixed with 100. mL of 0.100 M $\text{NaOH}$. What is the concentration of the resulting solution?

A. 0.0500 M

B. 0.100 M

Correct C. 0.200 M

D. 0.500 M

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 15

A 0.500 M solution of $\text{H}_2\text{SO}_4$ is mixed with 100. mL of 0.100 M $\text{Ba}$ \text{OH} $_2$. What is the concentration of the resulting solution?

A. 0.0500 M

Correct B. 0.100 M

C. 0.200 M

D. 0.500 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 16

The reaction between chlorine gas and potassium iodide produces iodine and potassium chloride. Write the balanced chemical equation for this reaction.

Correct A. \text{Cl}_2 + 2\text{KI} \rightarrow \text{I}_2 + 2\text{KCl}

B. \text{Cl}_2 + 2\text{KI} \rightarrow 2\text{KCl} + \text{I}_2

C. \text{Cl}_2 + \text{KI} \rightarrow \text{I}_2 + \text{KCl}

D. \text{Cl}_2 + \text{KI} \rightarrow 2\text{KCl} + \text{I}_2

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 17

A solution contains 0.5 M NaCl and 0.2 M CaCl2. Calculate the total concentration of chloride ions in the solution.

A. 0.5 M

Correct B. 1.0 M

C. 1.2 M

D. 1.5 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 18

A sample of a hydrocarbon has a density of 0.8 g/mL and a molar mass of 42 g/mol. What is the empirical formula of the hydrocarbon?

Correct A. C2H6

B. C3H8

C. C4H10

D. C5H12

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 19

A solution contains 0.1 M HCl and 0.2 M NaOH. Calculate the pH of the solution after the reaction is complete.

A. 0.5

Correct B. 1

C. 2

D. 3

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 20

A diagram of a titration setup is shown below. What is the purpose of the burette in this setup?

A. To measure the volume of the solution

B. To measure the pH of the solution

C. To mix the solution with the titrant

Correct D. To add the titrant to the solution

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 21

A 25.0 mL sample of 0.100 M HCl is titrated with 0.100 M NaOH. Calculate the volume of NaOH required to reach the equivalence point.

A. 12.5 mL

B. 25.0 mL

Correct C. 37.5 mL

D. 50.0 mL

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 22

A metal (X) reacts with chlorine gas to form a white solid. The reaction is as follows: X + Cl2 → XCl2. If 2.50 g of X reacts with 1.00 g of Cl2, what is the molar mass of X?

A. 50.0 g/mol

Correct B. 75.0 g/mol

C. 100 g/mol

D. 125 g/mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 23

A 2.00 L sample of a gas at 25°C and 1.00 atm is compressed to 0.500 L at the same temperature. What is the new pressure?

A. 2.00 atm

B. 4.00 atm

Correct C. 6.00 atm

D. 8.00 atm

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 24

A 0.100 M solution of NaOH is titrated with a 0.100 M solution of HCl. What is the pH of the solution after 25.0 mL of HCl has been added?

A. 1.00

B. 2.00

Correct C. 3.00

D. 4.00

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

Question 25

A metal (X) reacts with oxygen to form a white solid. The reaction is as follows: 4X + 3O2 → 2X2O3. If 2.50 g of X reacts with 1.00 g of O2, what is the molar mass of X?

A. 50.0 g/mol

Correct B. 75.0 g/mol

C. 100 g/mol

D. 125 g/mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics

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:

Chat with Support