POST UTME NOUN 2018 Chemistry | Objective

Are you preparing for POST UTME NOUN exams? Reviewing past questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2018 Chemistry (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1
Determine the number of moles of CO2 produced when 2.5 g of calcium carbonate (CaCO3) is heated in a crucible.
A. 0.05 mol
Correct B. 0.1 mol
C. 0.15 mol
D. 0.2 mol

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 2
A 2.5 L flask contains 0.5 mol of an ideal gas at 27°C. Calculate the pressure of the gas u\sing the ideal gas law.
A. 1.2 atm
B. 1.5 atm
Correct C. 2.0 atm
D. 2.5 atm

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 3
A solution contains 0.2 mol of NaCl in 2 L of water. What is the molarity of the solution?
A. 0.1 M
Correct B. 0.2 M
C. 0.3 M
D. 0.4 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 4
A diagram of a titration setup is shown below. If 25 mL of 0.1 M HCl is required to reach the equivalence point, what is the concentration of the NaOH solution?
A. 0.05 M
Correct B. 0.1 M
C. 0.15 M
D. 0.2 M

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 5
A 2.5 L flask contains 0.5 mol of an ideal gas at 27°C. Calculate the number of molecules of the gas u\sing the ideal gas law.
A. 1.5 x 10^22
B. 2.0 x 10^22
Correct C. 2.5 x 10^22
D. 3.0 x 10^22

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 6
A 0.1 M solution of NaOH is titrated with 0.1 M HCl. If 25 mL of HCl is required to reach the equivalence point, what is the pH of the resulting solution?
A. 7
Correct B. 9
C. 11
D. 13

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 7
A sample of water contains 10 ppm of dissolved oxygen. What is the concentration of oxygen in the water in mg/L?
Correct A. 10
B. 20
C. 30
D. 40

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 8
A 2 M solution of HCl is mixed with a 2 M solution of NaOH. What is the pH of the resulting solution?
A. 0
B. 1
C. 2
Correct D. 3

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 9
A sample of soil contains 20% clay, 30% silt, and 50% sand. What is the percentage of the soil that is finer than 0.05 mm?
A. 10
Correct B. 20
C. 30
D. 40

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 10
A 1 M solution of NaOH is titrated with 1 M HCl. If 25 mL of HCl is required to reach the equivalence point, what is the concentration of NaOH in the resulting solution?
Correct A. 0.1 M
B. 0.5 M
C. 1 M
D. 2 M

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 11
A metal oxide is reduced to its corresponding metal by heating in a stream of hydrogen gas. Which of the following metals is most likely to be produced?
A. Zn
B. Fe
Correct C. Cu
D. Ag

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 12
A solution of sodium chloride is electrolyzed u\sing a platinum electrode. What is the expected product at the cathode?
Correct A. H2
B. O2
C. Na
D. Cl2

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 13
A mixture of 2.5 g of sodium hydroxide and 2.5 g of sodium carbonate is dissolved in 100 mL of water. What is the pH of the resulting solution?
A. 9
Correct B. 10
C. 11
D. 12

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 14
A solution of 0.1 M sodium hydroxide is titrated with 0.1 M hydrochloric acid. What is the pH of the resulting solution after 25 mL of hydrochloric acid has been added?
A. 7
B. 8
Correct C. 9
D. 10

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 15
A mixture of 1.0 g of an unknown hydrocarbon and 1.0 g of an unknown alcohol is dissolved in 100 mL of water. What is the expected product of the reaction between the hydrocarbon and the alcohol?
Correct A. ester
B. aldehyde
C. ketone
D. alcohol

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 16
A solution of 0.1 M sodium hydroxide is titrated with 0.1 M hydrochloric acid. What is the pH of the resulting solution after 50 mL of hydrochloric acid has been added?
A. 7
B. 8
C. 9
Correct D. 10

Correct Answer: D

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 17
A mixture of 2.5 g of sodium hydroxide and 2.5 g of sodium carbonate is dissolved in 100 mL of water. What is the expected product of the reaction between the sodium hydroxide and the sodium carbonate?
Correct A. sodium bicarbonate
B. sodium carbonate
C. sodium hydroxide
D. carbon dioxide

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 18
A solution of 0.1 M sodium hydroxide is titrated with 0.1 M hydrochloric acid. What is the pH of the resulting solution after 75 mL of hydrochloric acid has been added?
A. 7
B. 8
Correct C. 9
D. 10

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 19
A mixture of 1.0 g of an unknown hydrocarbon and 1.0 g of an unknown alcohol is dissolved in 100 mL of water. What is the expected product of the reaction between the hydrocarbon and the alcohol?
Correct A. ester
B. aldehyde
C. ketone
D. alcohol

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 20
A solution of 0.1 M sodium hydroxide is titrated with 0.1 M hydrochloric acid. What is the pH of the resulting solution after 100 mL of hydrochloric acid has been added?
A. 7
B. 8
C. 9
D. 10

Correct Answer: VIEW ANSWER

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 21
The rate cons\tant of a first-order reaction is given by the equation k = Ae^\( -Ea/RT \). If the activation energy Ea is 100 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 10^6 s^-1
B. 1.0 x 10^7 s^-1
Correct C. 1.0 x 10^8 s^-1
D. 1.0 x 10^9 s^-1

Correct Answer: C

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 22
The half-life of a radioactive subs\tance is 5 years. If a sample of the subs\tance initially contains 100 g, what is the mass of the subs\tance remaining after 10 years?
Correct A. 12.5 g
B. 25 g
C. 50 g
D. 100 g

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 23
The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. If 2.0 mol of CO2(g) is produced at 298 K, what is the total enthalpy change for the reaction?
Correct A. -787 kJ
B. -393.5 kJ
C. -196.75 kJ
D. -393.5 kJ/mol

Correct Answer: A

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 24
The atomic radius of a certain element is 100 pm. If the element has an atomic number of 20, what is the number of protons in the nucleus of the atom?
A. 10
Correct B. 20
C. 30
D. 40

Correct Answer: B

Want to see the full step-by-step solution? Unlock AI Explanation & Analytics
Question 25
The density of a certain metal is 8.0 g/cm^3. If a sample of the metal has a mass of 50 g, what is the volume of the sample?
A. 6.25 cm^3
Correct B. 12.5 cm^3
C. 25 cm^3
D. 50 cm^3

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