POST UTME OSUSTECH 2018 Chemistry | Objective

Practice these randomly selected questions to test your readiness.

Question 1
A sample of a hydrocarbon has a molecular formula of C_4H_8. What is the type of hydrocarbon?
A. Alkane
B. Alkene
C. Alkyne
D. Aromatic hydrocarbon
Question 2
The reaction of sodium with water is highly exothermic. What is the balanced chemical equation for this reaction?
A. \( 2Na + 2H_2O \rightarrow 2NaOH + H_2 \)
B. \( 2Na + 2H_2O \rightarrow 2NaOH + O_2 \)
C. \( 2Na + 2H_2O \rightarrow 2NaOH + H_2O_2 \)
D. \( 2Na + 2H_2O \rightarrow 2NaOH + H_2O \)
Question 3
The reaction of sulfur with oxygen to form sulfur dioxide is an example of a combustion reaction. What is the balanced chemical equation for this reaction?
A. \( S + O_2 \rightarrow SO_2 \)
B. \( S + O_2 \rightarrow SO_3 \)
C. \( S + O_2 \rightarrow SO_4 \)
D. \( S + O_2 \rightarrow SO_5 \)
Question 4
Calculate the s\tandard enthalpy change (ΔH°) for the reaction: 2Al(s) + Fe2O3(s) → 2Fe(s) + Al2O3(s).
A. -853.9 kJ/mol
B. -853.1 kJ/mol
C. -853.5 kJ/mol
D. -853.7 kJ/mol
Question 5
Determine the number of moles of $\text{CO}_2$ produced when 2.50 g of $\text{CaC}_2$ is completely decomposed according to the equation: $\text{CaC}_2(s) \rightarrow \text{Ca}(s) + \text{C}(s) + \text{CO}_2(g)$.
A. 0.0500 mol
B. 0.100 mol
C. 0.150 mol
D. 0.200 mol
Question 6
A 2.00 L flask contains 0.500 atm of $\text{O}_2$ at 25°C. What is the partial pressure of $\text{O}_2$ in a mixture of $\text{O}_2$ and $\text{N}_2$ in the flask?
A. 0.250 atm
B. 0.500 atm
C. 0.750 atm
D. 1.00 atm
Question 7
A 25.0 mL sample of 0.100 M HCl is titrated with 0.100 M NaOH. Calculate the pH of the solution after the addition of 25.0 mL of NaOH.
A. 1.00
B. 2.00
C. 3.00
D. 4.00
Question 8
A 5.00 g sample of a metal is dissolved in 50.0 mL of 0.100 M HCl. What is the concentration of the resulting solution?
A. 0.100 M
B. 0.200 M
C. 0.300 M
D. 0.400 M
Question 9
The diagram below shows a redox reaction. Identify the oxidizing agent.
A. Zn
B. Cu
C. Ag
D. H2O
Question 10
A 5.00 g sample of a metal is dissolved in 50.0 mL of 0.100 M HCl. What is the concentration of the resulting solution?
A. 0.100 M
B. 0.200 M
C. 0.300 M
D. 0.400 M
Question 11
The diagram below shows a titration setup. Identify the subs\tance being titrated.
A. HCl
B. NaOH
C. H2SO4
D. NH3
Question 12
A 5.00 g sample of a metal is dissolved in 50.0 mL of 0.100 M HCl. What is the concentration of the resulting solution?
A. 0.100 M
B. 0.200 M
C. 0.300 M
D. 0.400 M
Question 13
A 25.0 mL sample of 0.100 M HCl is titrated with 0.100 M NaOH. Calculate the pH of the solution after the addition of 25.0 mL of NaOH.
A. ( 2.00 )
B. ( 3.00 )
C. ( 4.00 )
D. ( 5.00 )
Question 14
The s\tandard enthalpy of formation of CO2(g) is -393.5 kJ/mol. Calculate the s\tandard enthalpy of formation of CaCO3(s) from the following reaction: CaO(s) + CO2(g) → CaCO3(s).
A. -1206.5 kJ/mol
B. -1206.0 kJ/mol
C. -1207.0 kJ/mol
D. -1208.0 kJ/mol
Question 15
A 2.50 M solution of HCl is mixed with a 1.00 M solution of NaOH. What is the concentration of the resulting solution?
A. 1.25 M
B. 1.50 M
C. 2.00 M
D. 2.50 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: