Year :
1997
Title :
Chemistry
Exam :
WASSCE/WAEC MAY/JUNE
Paper 1 | Objectives
11 - 20 of 48 Questions
| # | Question | Ans |
|---|---|---|
| 11. |
An acid is a substance which in the presence of water produces A. salts B. oxygen C. effervescence D. hydroxonium ions E. hydrogen gas |
D |
| 12. |
Which of the following is a general method of preparing acids? A. Direct combination of constituent elements B. Double decomposition involving a salt solution C. Reaction between an anhydride and water D. Reaction between a base and an amphoteric oxide E. Dissolution of hydroxides followed by neutralization Detailed SolutionThere are several methods of preparation of acids. These include the following:1. By the reaction between an acidic oxide of a non-metal (acid anhydride) and water. SO2(g) + H2O(l) → H2SO3(aq) Trioxosulphate(IV) P4010(s) + 2H2O(l) → 4HPO3(aq) Trioxophosphate(V) |
|
| 13. |
Which of the following is a general method of preparing acids? A. Direct combination of constituent elements B. Reaction between a base and an amphoteric oxide C. Double decomposition involving a salt solution D. Reaction between an anhydride and water E. Dissolution of hydroxides followed by neutralization |
A |
| 14. |
The loss of molecules of water of crystallization to the atmosphere by some crystalline salts is known as A. efflorescence B. effervescence C. phosphorescence D. fluorescence E. deliquescence |
A |
| 15. |
Which of the following ions will migrate to the cathode during electrolysis? A. Zinc ions B. Chloride ions C. Sulphide ions D. Tetraoxosulphate (Vl) ions E. Trioxonitrate (V) ions |
A |
| 16. |
What quantity of electrons (in mole) is lost when one mole of iron (ll) ions is oxidized to iron (lll) ions? A. 5 mole B. 4 mole C. 3 mole D. 2 mole E. 1 mole |
E |
| 17. |
The common feature of reactions at the anode is that A. electrons are consumed B. oxidation is involved C. ions are reduced D. the electrode dissolves E. the electrolyte is diluted |
B |
| 18. |
From the following equations, what is the order of decreasing reactivity of X, Y and Z? Y (s) + X2+(aq) → Y2+(aq) + X(s) X(s) + Z2+(aq) → X2+(aq) + Z(s) A. X>Y>Z B. Y > X > Z C. Z > Y > X D. Y > Z > X E. X > Z > Y |
B |
| 19. |
What is the value of x in the following equation? MnO- 4 + 4H+ + xe- → MnO 2 + 2H2O A. 2 B. 3 C. 4 D. 7 E. 8 |
B |
| 20. |
If the value of ∆H for a reaction is negative, it means that the reaction is A. slow B. exothermic C. spontaneous D. irreversible E. not feasible |
B |
| 11. |
An acid is a substance which in the presence of water produces A. salts B. oxygen C. effervescence D. hydroxonium ions E. hydrogen gas |
D |
| 12. |
Which of the following is a general method of preparing acids? A. Direct combination of constituent elements B. Double decomposition involving a salt solution C. Reaction between an anhydride and water D. Reaction between a base and an amphoteric oxide E. Dissolution of hydroxides followed by neutralization Detailed SolutionThere are several methods of preparation of acids. These include the following:1. By the reaction between an acidic oxide of a non-metal (acid anhydride) and water. SO2(g) + H2O(l) → H2SO3(aq) Trioxosulphate(IV) P4010(s) + 2H2O(l) → 4HPO3(aq) Trioxophosphate(V) |
|
| 13. |
Which of the following is a general method of preparing acids? A. Direct combination of constituent elements B. Reaction between a base and an amphoteric oxide C. Double decomposition involving a salt solution D. Reaction between an anhydride and water E. Dissolution of hydroxides followed by neutralization |
A |
| 14. |
The loss of molecules of water of crystallization to the atmosphere by some crystalline salts is known as A. efflorescence B. effervescence C. phosphorescence D. fluorescence E. deliquescence |
A |
| 15. |
Which of the following ions will migrate to the cathode during electrolysis? A. Zinc ions B. Chloride ions C. Sulphide ions D. Tetraoxosulphate (Vl) ions E. Trioxonitrate (V) ions |
A |
| 16. |
What quantity of electrons (in mole) is lost when one mole of iron (ll) ions is oxidized to iron (lll) ions? A. 5 mole B. 4 mole C. 3 mole D. 2 mole E. 1 mole |
E |
| 17. |
The common feature of reactions at the anode is that A. electrons are consumed B. oxidation is involved C. ions are reduced D. the electrode dissolves E. the electrolyte is diluted |
B |
| 18. |
From the following equations, what is the order of decreasing reactivity of X, Y and Z? Y (s) + X2+(aq) → Y2+(aq) + X(s) X(s) + Z2+(aq) → X2+(aq) + Z(s) A. X>Y>Z B. Y > X > Z C. Z > Y > X D. Y > Z > X E. X > Z > Y |
B |
| 19. |
What is the value of x in the following equation? MnO- 4 + 4H+ + xe- → MnO 2 + 2H2O A. 2 B. 3 C. 4 D. 7 E. 8 |
B |
| 20. |
If the value of ∆H for a reaction is negative, it means that the reaction is A. slow B. exothermic C. spontaneous D. irreversible E. not feasible |
B |