Exam Body

Year

Subject

Paper Type

POST UTME GREENFIELD UNIVERSITY 2023 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 2023 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 at 25°C.

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 2

A 25 mL sample of 0.5 M H2SO4 is titrated with 0.5 M NaOH. Calculate the number of moles of H2SO4 used.

A. 0.025

Correct B. 0.05

C. 0.075

D. 0.1

Correct Answer: B

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

Question 3

The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. Calculate the s\tandard enthalpy of combustion of 1 mole of C6H12O6(s).

A. -2800

B. -2900

Correct C. -3000

D. -3100

Correct Answer: C

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

Question 4

A reaction is first-order with respect to A and second-order with respect to B. The rate cons\tant is 0.05 s^-1. If the initial concentrations of A and B are 0.1 M and 0.2 M, respectively, calculate the rate of reaction after 10 minutes.

A. 0.0001

B. 0.0005

C. 0.001

Correct D. 0.005

Correct Answer: D

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

Question 5

The diagram below shows a titration setup. Identify the part labeled A.

Correct A. A

B. B

C. C

D. D

Correct Answer: A

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

Question 6

The reaction of zinc metal with copper(II) sulfate solution is represented by the equation: Zn(s) + CuSO4(aq) → ZnSO4(aq) + Cu(s). What is the oxidation state of copper in the reac\tant and product?

Correct A. Cu: +2, Cu: +2

B. Cu: +1, Cu: +1

C. Cu: +2, Cu: 0

D. Cu: 0, Cu: +2

Correct Answer: A

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

Question 7

A 2.5 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

Correct B. 2.0

C. 3.0

D. 4.0

Correct Answer: B

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

Question 8

The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. What is the s\tandard enthalpy of formation of CO(g)?

Correct A. -110.5

B. -110.5

C. -110.5

D. -110.5

Correct Answer: A

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

Question 9

A sample of a polymer has a molecular weight of 100,000 g/mol. If the density of the polymer is 1.5 g/cm^3, what is the volume of the polymer sample?

Correct A. 66.7 cm^3

B. 66.7 cm^3

C. 66.7 cm^3

D. 66.7 cm^3

Correct Answer: A

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

Question 10

The diagram below shows the structure of a biomolecule. What is the function of the molecule?

Correct A. Transport of molecules across the cell membrane

B. Synthesis of proteins

C. Storage of genetic information

D. Regulation of cell growth

Correct Answer: A

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

Question 11

The rate cons\tant (k) for a first-order reaction is given by the equation: k = Ae^\( -Ea/RT \). If the activation energy (Ea) is 50 kJ/mol, the gas cons\tant (R) is 8.314 J/mol*K, and the temperature (T) is 300 K, what is the value of the rate cons\tant (k) if the pre-exponential factor (A) is 1.0 x 10^10 s^-1?

A. 1.0 x 10^7 s^-1

B. 1.0 x 10^8 s^-1

Correct C. 1.0 x 10^9 s^-1

D. 1.0 x 10^10 s^-1

Correct Answer: C

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

Question 12

A 0.1 M solution of HCl is titrated with a 0.1 M solution of NaOH. If 20 mL of NaOH is added, what is the pH of the resulting solution?

A. 1

Correct B. 2

C. 3

D. 4

Correct Answer: B

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

Question 13

The half-life of a radioactive subs\tance is 10 years. If the initial amount of the subs\tance is 100 g, what is the amount remaining after 20 years?

Correct A. 25 g

B. 50 g

C. 75 g

D. 100 g

Correct Answer: A

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

Question 14

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

Correct B. 500 g/mol

C. 1000 g/mol

D. 2000 g/mol

Correct Answer: B

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

Question 15

The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. What is the s\tandard enthalpy of combustion of methane (CH4(g))?

Correct A. -890.3 kJ/mol

B. -890.4 kJ/mol

C. -890.5 kJ/mol

D. -890.6 kJ/mol

Correct Answer: A

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

Question 16

The enthalpy change for the reaction 2Al(s) + Fe2O3(s) → Al2O3(s) + 2Fe(s) is -853.2 kJ/mol. What is the s\tandard enthalpy of formation of Al2O3(s)?

A. -421.6 kJ/mol

Correct B. -853.2 kJ/mol

C. -421.6 kJ/mol

D. -853.2 kJ/mol

Correct Answer: B

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

Question 17

A solution of 0.1 M NaCl is prepared by dissolving 6.0 g of NaCl in 1.0 L of water. What is the concentration of Cl- ions in the solution?

A. 0.1 M

Correct B. 0.05 M

C. 0.1 M

D. 0.05 M

Correct Answer: B

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

Question 18

The rate cons\tant for the first-order reaction A → B is 0.05 min^-1. What is the half-life of the reaction?

Correct A. 13.9 min

B. 27.8 min

C. 13.9 min

D. 27.8 min

Correct Answer: A

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

Question 19

A 0.1 M solution of HCl is prepared by dissolving 6.0 g of HCl in 1.0 L of water. What is the pH of the solution?

Correct A. 1.0

B. 2.0

C. 1.0

D. 2.0

Correct Answer: A

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

Question 20

The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. What is the s\tandard enthalpy of combustion of methane?

Correct A. -890.3 kJ/mol

B. -393.5 kJ/mol

C. -890.3 kJ/mol

D. -393.5 kJ/mol

Correct Answer: A

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

Question 21

The polymerization of styrene to polystyrene is an example of a

A. condensation polymerization

Correct B. addition polymerization

C. esterification

D. hydrolysis

Correct Answer: B

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

Question 22

The atomic radius of an element increases down a group in the periodic table due to the

A. increase in atomic number

B. increase in atomic mass

Correct C. increase in electron shielding

D. increase in nuclear charge

Correct Answer: C

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

Question 23

The reaction between sodium hydroxide and acetic acid is an example of a

Correct A. neutralization reaction

B. esterification reaction

C. hydrolysis reaction

D. oxidation reaction

Correct Answer: A

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

Question 24

The molar mass of a subs\tance is the mass of one mole of the subs\tance in grams, expressed in units of

A. ki\lograms

Correct B. grams

C. milligrams

D. micrograms

Correct Answer: B

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

Question 25

The diagram below shows a titration setup. What is the purpose of the burette?

Correct A. to measure the volume of the titrant

B. to measure the volume of the analyte

C. to mix the titrant and analyte

D. to separate the titrant and analyte

Correct Answer: A

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