Exam Body

Year

Subject

Paper Type

POST UTME GREENFIELD UNIVERSITY 2019 Chemistry | Objective

Are you preparing for POST UTME GREENFIELD 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

Determine the pH of a 0.1 M solution of HCl after 10 mL of 1 M NaOH has been added to 20 mL of the HCl solution.

Correct A. 2

B. 3

C. 4

D. 5

Correct Answer: A

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

Question 2

A 25 mL sample of a polymer solution containing 0.5 g/mL of polyethylene oxide (PEO) is dissolved in 75 mL of water. Calculate the number-average molecular weight of the PEO.

A. 1000

B. 2000

Correct C. 3000

D. 4000

Correct Answer: C

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

Question 3

A diagram of a titration setup is shown below. If 25 mL of 0.1 M NaOH is required to reach the equivalence point, what is the concentration of the HCl solution?

A. 0.05 M

Correct B. 0.1 M

C. 0.2 M

D. 0.5 M

Correct Answer: B

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

Question 4

A 0.1 M solution of HCl is titrated with 0.1 M NaOH. If 25 mL of NaOH is required to reach the equivalence point, what is the volume of the HCl solution?

A. 25 mL

Correct B. 50 mL

C. 75 mL

D. 100 mL

Correct Answer: B

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

Question 5

A diagram of a chemical apparatus setup is shown below. If the concentration of the solution is 0.1 M, what is the volume of the solution?

A. 10 mL

B. 25 mL

Correct C. 50 mL

D. 100 mL

Correct Answer: C

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

Question 6

A polymer is formed by the condensation reaction between two monomers, A and B. If the molecular weight of the polymer is 100,000 g/mol, and the molecular weights of the monomers are 20,000 g/mol and 30,000 g/mol, respectively, what is the average degree of polymerization?

A. 2

Correct B. 3

C. 4

D. 5

Correct Answer: B

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

Question 7

A solution of sulfuric acid (H2SO4) is titrated with a solution of sodium hydroxide (NaOH). The initial concentration of the acid is 0.1 M, and the initial concentration of the base is 0.2 M. If 20 mL of the base is added to 100 mL of the acid, what is the pH of the resulting solution?

A. 1

B. 2

C. 3

Correct D. 4

Correct Answer: D

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

Question 8

A sample of a non-metallic solid is heated in a crucible until it melts. The resulting liquid has a boiling point of 100°C. What is the identity of the non-metallic solid?

A. Sulfur

Correct B. Phosphorus

C. Arsenic

D. Antimony

Correct Answer: B

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

Question 9

A metal is extracted from its ore u\sing a reduction reaction. The ore is first roasted to convert it into a more reactive form. What is the purpose of roasting the ore?

Correct A. To increase the reactivity of the ore

B. To decrease the reactivity of the ore

C. To convert the ore into a more stable form

D. To remove impurities from the ore

Correct Answer: A

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

Question 10

A solution of a strong acid is titrated with a solution of a strong base. The initial concentration of the acid is 0.5 M, and the initial concentration of the base is 0.3 M. If 15 mL of the base is added to 50 mL of the acid, what is the pH of the resulting solution?

A. 1

B. 2

C. 3

Correct D. 4

Correct Answer: D

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

Question 11

Determine the number of moles of oxygen gas (O2) produced at s\tandard temperature and pressure (STP) when 2.5 moles of hydrogen gas (H2) react with excess oxygen gas according to the equation: 2H2 + O2 → 2H2O.

Correct A. 1.25 moles

B. 2.5 moles

C. 5 moles

D. 10 moles

Correct Answer: A

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

Question 12

A 2.5 L flask contains 0.5 mol of an ideal gas at a temperature of 300 K. If the gas is heated to 400 K at cons\tant volume, what is the new pressure of the gas?

A. 1.5 atm

B. 2.0 atm

Correct C. 2.5 atm

D. 3.0 atm

Correct Answer: C

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

Question 13

A solution contains 0.1 M NaCl and 0.2 M CaCl2. What is the total concentration of chloride ions in the solution?

A. 0.1 M

B. 0.2 M

Correct C. 0.3 M

D. 0.4 M

Correct Answer: C

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

Question 14

A 1.0 L flask contains 0.5 mol of an ideal gas at a temperature of 300 K. If the gas is compressed to 0.5 L at cons\tant temperature, what is the new pressure of the gas?

A. 2.0 atm

B. 3.0 atm

Correct C. 4.0 atm

D. 5.0 atm

Correct Answer: C

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

Question 15

A 2.0 L flask contains 1.0 mol of an ideal gas at a temperature of 400 K. If the gas is heated to 500 K at cons\tant pressure, what is the new volume of the gas?

A. 2.5 L

B. 3.0 L

C. 3.5 L

Correct D. 4.0 L

Correct Answer: D

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

Question 16

A solution contains 0.1 mol of a weak electrolyte, X, in 1 L of solution. The conductivity of the solution is 0.005 S/m. Calculate the molar conductivity of X at 25°C.

Correct A. 0.05 S m^2 mol^-1

B. 0.1 S m^2 mol^-1

C. 0.2 S m^2 mol^-1

D. 0.05 S m^2 mol^-1

Correct Answer: A

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

Question 17

A mixture of 0.1 mol of NaCl and 0.1 mol of CaCl2 is dissolved in 1 L of water. Calculate the molar conductivity of the solution at 25°C.

A. 0.05 S m^2 mol^-1

Correct B. 0.1 S m^2 mol^-1

C. 0.2 S m^2 mol^-1

D. 0.05 S m^2 mol^-1

Correct Answer: B

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

Question 18

A solution contains 0.1 mol of a strong electrolyte, X, in 1 L of solution. The conductivity of the solution is 0.01 S/m. Calculate the molar conductivity of X at 25°C.

Correct A. 0.1 S m^2 mol^-1

B. 0.2 S m^2 mol^-1

C. 0.05 S m^2 mol^-1

D. 0.05 S m^2 mol^-1

Correct Answer: A

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

Question 19

A mixture of 0.1 mol of NaCl and 0.1 mol of CaCl2 is dissolved in 1 L of water. Calculate the molar conductivity of the solution at 25°C.

A. 0.05 S m^2 mol^-1

Correct B. 0.1 S m^2 mol^-1

C. 0.2 S m^2 mol^-1

D. 0.05 S m^2 mol^-1

Correct Answer: B

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

Question 20

A solution contains 0.1 mol of a weak electrolyte, X, in 1 L of solution. The conductivity of the solution is 0.005 S/m. Calculate the molar conductivity of X at 25°C.

Correct A. 0.05 S m^2 mol^-1

B. 0.1 S m^2 mol^-1

C. 0.2 S m^2 mol^-1

D. 0.05 S m^2 mol^-1

Correct Answer: A

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

Question 21

Calculate the s\tandard enthalpy of formation of CO2(g) from the following data: ΔH°f(CO2(g)) = -393.5 kJ/mol, ΔH°f(C) = 0 kJ/mol, ΔH°f(O2(g)) = 0 kJ/mol.

A. -393.5 kJ/mol

Correct B. -393.5 kJ/mol + 0 kJ/mol + 0 kJ/mol

C. -393.5 kJ/mol - 0 kJ/mol - 0 kJ/mol

D. -393.5 kJ/mol + 0 kJ/mol

Correct Answer: B

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

Question 22

A 2.0 M solution of HCl is mixed with a 2.0 M solution of NaOH. What is the resulting concentration of HCl after the reaction is complete?

A. 0 M

B. 2.0 M

Correct C. 1.0 M

D. 4.0 M

Correct Answer: C

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

Question 23

The reaction 2NO(g) + O2(g) → 2NO2(g) has a rate cons\tant of 0.0050 s^-1 at 298 K. What is the rate of reaction if the initial concentrations of NO and O2 are both 0.100 M?

Correct A. 1.0 x 10^-5 M/s

B. 1.0 x 10^-4 M/s

C. 1.0 x 10^-3 M/s

D. 1.0 x 10^-2 M/s

Correct Answer: A

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

Question 24

A sample of CO2 gas is collected over water at 25°C and 1 atm. What is the partial pressure of CO2 in the gas mixture?

A. 1 atm

B. 0.5 atm

Correct C. 0.75 atm

D. 0.25 atm

Correct Answer: C

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

Question 25

A 1.0 M solution of HCl is mixed with a 1.0 M solution of NaOH. What is the resulting concentration of HCl after the reaction is complete?

A. 0 M

Correct B. 1.0 M

C. 0.5 M

D. 2.0 M

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