Exam Body

Year

Subject

Paper Type

UTME 2021 Chemistry | Objective

Are you preparing for UTME exams? Reviewing past questions is one of the most effective ways to guarantee a high score. This practice hub features authentic 2021 Chemistry (Objective) questions designed to simulate the real exam environment.

Practice these randomly selected questions to test your readiness.

Question 1

When steam is passed through red hot carbon, which of the following are produced?

A. Hydrogen, oxygen and carbon(IV) oxide

B. Hydrogen and carbon(IV) oxide

Correct C. Hydrogen and carbon(II) oxide

D. Hydrogen and trioxocarbonate(IV) acid

Correct Answer: C

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

Question 2

Which of the following contains an efflorescent, a deliquescent and a hygroscopic substance respectively?

Correct A. \( \mathrm{Na}_{2}SO_{3}, \text{Concentrated} \text{ } \mathrm{H}_{2} \mathrm{SO}_{4}, \mathrm{CaCl}_{2} \)

B. \( \mathrm{Na}_{2} \mathrm{CO}_{3}, \mathrm{H}_{2} \mathrm{O}, \mathrm{FeSO}_{4}, 7 \mathrm{H}_{2} \mathrm{O}, \text{Concentrated} \text{ } \mathrm{H}_{2}, \mathrm{SO}_{4}, \)

C. \( \mathrm{C} . \mathrm{Na}_{2}\mathrm{CO}_{3}, \mathrm{IOH}_{2} \mathrm{O}, \mathrm{FeCl}_{2}, \text{Concentrated} \text{ } \mathrm{H}_{2}, \mathrm{SO}_{4} \)

D. \( \text{Concentrated} \text{ } \mathrm{H}_{2}, \mathrm{SO}_{4}, \mathrm{FeSO}, 7 \mathrm{H}_{2} \mathrm{O}, \mathrm{MgCl}_{2} \)

Correct Answer: A

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

Question 3

The tabulated results below were obtained by titrating \( 10.0\text{ cm}^3 \) of water with soap. The titration was repeated with the same sample of water after boiling. \( \begin{array}{|l|c|c|} \hline \text{ } & \text{Before boiling} & \text{After boiling} \\ \hline \text{Final } (\text{cm}^3) & 25.0 & 20.0 \\ \hline \text{Initial } (\text{cm}^3) & 0.0 & 15.0 \\ \hline \end{array} \) The ratio of permanent to temporary hardness in the water titration process is

A. 1:5

Correct B. 1:4

C. 4:1

D. 5:1

Correct Answer: B

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

Question 4

The exhaust fumes from a garage in a place that uses petrol of high sulphur content are bound to contain

A. \( CO \text{ and } SO \)

Correct B. \( CO \text{ and } SO_2 \)

C. \( CO, SO \text{ and } SO_3 \)

D. \( CO \text{ and } H_2 \)

Correct Answer: B

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

Question 5

Oxygen demanding wastes are considered to be a water pollutant because they

Correct A. deplete oxygen which is necessary for the survival of aquatic organisms

B. increase oxygen which is necessary for the survival of aquatic organisms

C. increase other gaseous substances which are necessary for the survival of aquatic organism

D. deplete other gaseous species which are necessary for the survival of aquatic organisms

Correct Answer: A

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

Question 6

Which of the following will react further with oxygen to form a higher oxide?

A. \( NO \text{ and } H_2O \)

B. \( CO \text{ and } \mathrm{CO}_{2} \)

Correct C. \( \mathrm{SO}_{2} \text{ and } NO \)

D. \( CO \text{ and } H_2O \)

Correct Answer: C

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

Question 7

In the course of an experiment, two gases \( X \) and \( Y \) were produced. X turned wet lead ethanoate to black and Y bleached moist litmus paper. What are the element(s) in each of the gases \( X \) and \( Y \) respectively?

Correct A. \( \mathrm{H} \) and \( \mathrm{S} \); \( \mathrm{Cl} \)

B. \( \mathrm{H} \) and \( \mathrm{O} \); \( \mathrm{Cl} \)

C. \( \mathrm{H} \) and \( \mathrm{S} \); \( \mathrm{C} \) and \( \mathrm{O} \)

D. \( \mathrm{H} \) and \( \mathrm{Cl} \); \( \mathrm{S} \) and \( \mathrm{O} \)

Correct Answer: A

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

Question 8

The number of molecules of carbon(IV) oxide produced when 10.0 g of CaCO3 is treated with \( 0.2 dm^3 \) of 1 M HCl in the equation \( \mathrm{CaCO}_3 + 2 \mathrm{HCl} \rightarrow \mathrm{CaCl}_2 + \mathrm{H}_2O + \mathrm{CO}_2 \text{ is }\) \([ \mathrm{Ca} \text{= 40.0}, \mathrm{H} \text{= 1}, \mathrm{Cl} \text{= 35.5} ] \)

Correct A. \( 1.00 \times 10^{23} \)

B. \( 6.02 \times 10^{23} \)

C. \( 6.02 \times 10^{n} \)

D. \( 6.02 \times 10^{n} \)

Correct Answer: A

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

Question 9

In the reaction \( \mathrm{CaC}_2(s) + 2 \mathrm{H}_2O \rightarrow \mathrm{Ca(OH)}_2(s) + \mathrm{C}_2H_2(g) \) what is the mass of solid calcium needed to produce \( 1000 cm^3 \) of acetylene gas at S.T.P.?

A. 3.8 g

Correct B. 2.9 g

C. 2.0 g

D. 1.0 g

Correct Answer: B

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

Question 10

If the quantity of oxygen occupying a 2.76 litre container at a pressure of 0.825 atmosphere and 300 K is reduced by one half, what is the pressure exerted by the remaining gas?

A. 1.650 atm

B. 0.825 atm

Correct C. 0.413 atm

D. 0.275 atm

Correct Answer: C

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

Question 11

Which of the following substances has the lowest vapour density?

A. Ethanoic acid

B. Propanol

C. Dichloromethane

Correct D. Ethanal

Correct Answer: D

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

Question 12

If \( d \) represents the density of a gas and \( k \) is a constant, the rate of gaseous diffusion \( r \) is related to \( d \) by the equation

A. \( r = kd \)

B. \( r = kd^2 \)

Correct C. \( r = k/d \)

D. \( r = kd^2 \)

Correct Answer: C

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

Question 13

Which of the following compounds will give a precipitate with an aqueous ammoniacal solution of copper(I) chloride?

A. \( \mathrm{CH}_3\mathrm{CH} = \mathrm{CHCH} \)

B. \( \mathrm{CH}_{3}\mathrm{C} = \mathrm{CCH} \)

Correct C. \( \mathrm{HC} = \mathrm{C} - \mathrm{CH}_3 \)

D. \( \mathrm{CH}_2 = \mathrm{CH} - \mathrm{CH} = \mathrm{CH}_2 \)

Correct Answer: C

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

Question 14

The efficiency of petrol as a fuel in high compression internal combustion engines improves with an increase in the amount of

Correct A. branched chain alkanes

B. straight chain alkanes

C. cycloalkanes

D. halogenated hydrocarbons

Correct Answer: A

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

Question 15

A palm wine seller stopped a bottle of his palm wine in his stall and after a few hours the bottle exploded. Which of the following equations represents the enzyme's reaction that occurred?

Correct A. \( \mathrm{C}_6\mathrm{H}_{12}\mathrm{O} \rightarrow 2 \mathrm{C}_6\mathrm{H}_{14} + 2 \mathrm{CO} + 2 \mathrm{CO}_2 \)

B. \( \mathrm{C}_6\mathrm{H}_{12}\mathrm{OH} \rightarrow \mathrm{CH}_{2} = \mathrm{CH}_2 + \mathrm{H}_2 \mathrm{O} \)

C. \( \mathrm{C}_6\mathrm{H}_{12}\mathrm{OH} + \) dil \( \mathrm{H}_2\mathrm{SO}_4 \rightarrow \mathrm{C}_2 \mathrm{H}_3\mathrm{O} \)

D. \( \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 \rightarrow \mathrm{C}_2\mathrm{H}_5\mathrm{OH} + \mathrm{CO}_2 \)

Correct Answer: A

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

Question 16

Ethanol reacts with aqueous sodium monooxoiodate(I) to give a bright yellow solid with a characteristic smell. The product is

A. trichloromethane

Correct B. triodomethane

C. iodoethane

D. ethanal

Correct Answer: B

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

Question 17

The most volatile fraction obtained from fractional distillation of crude petroleum contains

A. butane, propane and kerosene

B. butane, propane and petrol

C. ethane, methane and benzene

Correct D. methane, ethane and propane

Correct Answer: D

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

Question 18

Local black soap is made by boiling palm oil with liquid extract of ash. The function of the ash is to provide the

A. acid

B. ester of alkanoic acid

Correct C. alkali

D. alkanol

Correct Answer: C

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

Question 19

Synthetic rubber is made by polymerization of

Correct A. 2-methyl buta -1,3-diene

B. 2-methylbut-1,2-diene

C. 2-methyl but-1-ene

D. 2-methyl but-2-ono

Correct Answer: A

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

Question 20

An increase in temperature causes an increase in the pressure of a gas because there is an increase in the

Correct A. average velocity of the molecules

B. nuclei of collisions between the molecules

C. density of the molecules

D. free mean path between each molecule and the other

Correct Answer: A

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

Question 21

The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354 K resulting in the crystals melting. The forces are known as

A. coulombic

B. ionic

C. covalent

Correct D. van der Waals

Correct Answer: D

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

Question 22

A metallic ion X with an inert gas structure contains 18 electrons. How many protons are there in this ion?

Correct A. 20

B. 18

C. 16

D. 2

Correct Answer: A

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

Question 23

Which of the following physical properties decreases across the Periodic Table?

A. Ionization potential

B. Electron affinity

C. Electronegativity

Correct D. Atomic radius

Correct Answer: D

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

Question 24

What are the possible oxidation numbers for an element if its atomic number is 17?

Correct A. -1 and 7

B. -1 and 6

C. -3 and 5

D. -2 and 6

Correct Answer: A

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

Question 25

The energy change accompanying the addition of an electron to a gaseous atom is called

A. first ionization energy

B. second ionization energy

Correct C. electron affinity

D. electronegativity

Correct Answer: C

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