Waec Chemistry Past Questions For Year 2007
Question 16
Which of the following statements is true of the molecules of a gas under ideal conditions? The molecules
- A. move at random
- B. undergo inelastic collisions
- C. attract each other
- D. occupy a large volume
Question 17
Which of the following gases is light than air?
- A. CO2
- B. SO2
- C. HCI
- D. NH3
Question 18
When air is successively passed through sodium hydroxide solution, alkaline pyrogallol and then concentrated tetraoxosulphate (VI) acid, its remaining components are
- A. oxygen and water vapour
- B. oxygen and nitrogen
- C. carbon (IV) acid and noble gases
- D. nitrogen and noble gases
Question 19
Which of these cell notations is the correct representation of a Daniell cell?
- A. Zn(s) / Zn2+(aq) // Cu2+(aq)/Cu(s)
- B. Cu(s) / CU2+(aq) // Zn2+(aq) / Zn(s)
- C. Zn2+(aq) / Zn(s) // Cu2+(aq) /Cu(s)
- D. Cu2+(aq) / Cu(s) // Zn(s) / Zn2+(aq)
Question 20
Consider the reaction represented by the following equation: N2(g) + 3H2(g) ⇌ 2NH3(g); ∆H = - 92kJmol1. Finely divided iron is used as catalyst in the reaction in order to
- A. lower the value of ∆H
- B. increase the time for attainment of equilibrium
- C. shorten the time for attainment of equilibrium
- D. decrease the yield of ammonia
