POST UTME ESUT 2021 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
The diagram below shows a simple electrolytic cell. What is the purpose of the salt bridge in this setup?
A. To maintain electrical neutrality
B. To facilitate the flow of ions
C. To prevent the mixing of solutions
D. To increase the voltage of the cell
Question 2
Determine the number of moles of $\text{CO}_2$ produced when 2.50 g of $\text{CaCO}_3$ is decomposed at cons\tant pressure.
A. 0.0250 mol
B. 0.0500 mol
C. 0.100 mol
D. 0.200 mol
Question 3
A solution of NaOH is prepared by dissolving 10 g of NaOH in 100 mL of water. What is the concentration of the solution in molarity?
A. 0.1 M
B. 0.5 M
C. 1.0 M
D. 2.0 M
Question 4
A 10.0 g sample of an unknown hydrocarbon is burned in a combustion apparatus. The volume of carbon dioxide gas produced is 22.5 L at 25°C and 1 atm. What is the empirical formula of the hydrocarbon?
A. C2H4
B. C3H6
C. C4H8
D. C5H10
Question 5
A 1.0 M solution of HCl is titrated with 0.5 M NaOH. If 25 mL of HCl is required to reach the equivalence point, what is the volume of NaOH required to reach the equivalence point?
A. 12.5 mL
B. 25 mL
C. 50 mL
D. 100 mL
Question 6
A polymer is made from a monomer with the molecular formula C5H8. If the polymer has a degree of polymerization of 500, what is the molar mass of the polymer?
A. 2500 g/mol
B. 25000 g/mol
C. 250000 g/mol
D. 2500000 g/mol
Question 7
A solution of 0.1 M NaOH is titrated with 0.1 M HCl. What is the pH of the solution after 25 mL of HCl has been added?
A. 1
B. 2
C. 3
D. 4
Question 8
A 2.5 g sample of an unknown metal is heated in a crucible until it melts. The mass of the crucible and metal is 2.8 g. The mass of the crucible alone is 2.2 g. What is the density of the metal?
A. 2.5 g/cm^3
B. 3.5 g/cm^3
C. 4.5 g/cm^3
D. 5.5 g/cm^3
Question 9
A 2.0 M solution of hydrochloric acid (HCl) is mixed with a 1.0 M solution of sodium hydroxide (NaOH). If 50 mL of the HCl solution is mixed with 50 mL of the NaOH solution, what is the concentration of the resulting solution?
A. 0.5 M
B. 1.0 M
C. 1.5 M
D. 2.0 M
Question 10
A metal (M) reacts with chlorine gas to form a white solid. The reaction is as follows: M + Cl2 → MX2. If 2.5 g of M reacts with 1.5 g of Cl2, what is the molar mass of M?
A. 50 g/mol
B. 75 g/mol
C. 100 g/mol
D. 125 g/mol
Question 11
The reaction between sodium and chlorine is highly exothermic and produces a white solid. The balanced equation is: 2Na(s) + Cl2(g) → 2NaCl(s). What is the type of reaction that occurs in this process?
A. Synthesis reaction
B. Decomposition reaction
C. Combination reaction
D. Displacement reaction
Question 12
A $2.0$ L solution contains $1.0$ mol of $NaOH$. What is the concentration of $OH^-$ ions in the solution?
A. 0.25 M
B. 0.50 M
C. 0.75 M
D. 1.0 M
Question 13
Determine the number of moles of $CO_2$ produced when 2.5 g of $CaC_2$ is heated in a stream of $CO_2$ gas at $25^circ C$ and 1 atm.
A. 0.05 mol
B. 0.10 mol
C. 0.15 mol
D. 0.20 mol
Question 14
A 2.5 g sample of a polymer is dissolved in 50 mL of a solvent. The solution is then diluted to 100 mL. What is the concentration of the polymer solution in g/L?
A. 0.025 g/L
B. 0.05 g/L
C. 0.1 g/L
D. 0.2 g/L
Question 15
A solution of a salt is prepared by mixing 10 mL of 0.1 M NaOH with 20 mL of 0.1 M HCl. What is the concentration of the resulting solution?
A. 0.05 M
B. 0.1 M
C. 0.15 M
D. 0.2 M

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: