Waec Chemistry Past Questions For Year 2008
Question 21
Which of the following set of equations could be used to represent the standard enthalpy of formation of glucose?
- A. 6C (s) + 6H 2(g) + 3O2(g) → C 6H12O6(s)
- B. 6CO2(g) + 6H2O (l) → C6H12O6(s) + 6O 2(g)
- C. 6C(g) + 6H 2(g) + 3O2(g) → C6H12O 6(s)
- D. 6C(g) + 6H 2(g) + 3O2(g) → C 6H 12O 6(aq)
Question 22
Diamond does not conduct electricity because it?
- A. has no free valence electrons
- B. is a giant molecule
- C. contains no bonded electrons
- D. is a solid at room temperature
Question 23
The collision theory proposes that
- A. reactants collide more frequently to bring about reduction in the reaction rate
- B. all collisions of reactants are effective
- C. reactants must collide with a certain minimum amount of energy to from products
- D. the fewer the collisions the faster the reaction rate
Question 24
Consider the equilibrium reaction represented by the equation: 2SO2(g) + O2(g) ⇌ 2SO3(g) ∆H = - 197 kJmol-1. At equilibrium, increase in the total pressure of the system brings about
- A. decrease in rate of the reaction of the system
- B. decrease in temperature of the system
- C. increase in temperature of SO3
- D. increase in concentration of SO2
Question 25
The high solubility of ethanol in water is due to its
- A. low boiling point
- B. low freezing point
- C. covalent nature
- D. hydrogen bonding
