Waec Chemistry Past Questions For Year 2004
Question 16
Two solutions containing Pb2+ and AI3+ respectively can be distingusihed using
- A. NaOH(aq)
- B. NH3(aq)
- C. conc. HCI3
- D. conc. HCI
Question 17
What quantity of electrons in moles is needed to discharge two moles of aluminum from aluminum oxide (AI 2O3)
- A. 1
- B. 2
- C. 4
- D. 6
Question 18
Which of the following subtances will not produce effervescence with dilute hydeochloric acid?
- A. Copper (ll) trioxocarbonate (IV)
- B. Potassium hydrogentrioxocarbonate (lV)
- C. Zinc granules
- D. Sodium chloride
Question 19
What are the values of x, y and z respectively in the following in the following equation? MnO 2(s) + xHCI(aq) → MnCI2(g) + yHO(l) + zCI2(g)
- A. 4,1,2
- B. 1,2,1
- C. 2,1,2
- D. 4,2,1
Question 20
The reaction that takes place at the cathode when an aqueous solution of NaCI is electrolysed using carbon electrodes is
- A. 2H+2(g) + 2e- → H2(g)
- B. Na+2(g) + e- → Na(s)
- C. 4OH- → 2H2O(l) + O2(g) +4e-
- D. 2CI- → CI2(g) + 2e-
