Year :
1989
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
11 - 20 of 49 Questions
| # | Question | Ans |
|---|---|---|
| 11. |
The gaseous pollutant sulphur (IV)oxide is most likely to be detected in fairly reasonable quantities in the area around a plant for the A. extraction of aluminium from bauxite B. production of margarine C. smelting of copper D. production of chlorine from brine |
C |
| 12. |
Calcium hydroxide is added in the treatment of town water supply to A. kill bacteria in the water B. facilitate coagulation of organic particles C. facilitate sedimentation D. improve the taste of the water |
B |
| 13. |
A hydrated salt of formula MSO4.xH2 O CONTAINS 45.3% by mass of water of crystalisation. Calculate the value of x [M = 56, S = 32, O = 16, H = 1 ] A. 3 B. 5 C. 7 D. 10 |
C |
| 14. |
Using 50 cm 3 of 1 M potassium hydroxide and 100cm 3 of 1 M tetraoxosulphate (VI) acid, calculate the respective volumes in cm 3 of base and acid that would be required to produce the maximum amount of potassium tetraoxosulphate (IV) [ = 39, S = 32, O = 16, H = 1] A. 50, 50 B. 25, 50 C. 50, 25 D. 25, 25 |
C |
| 15. |
A solution of calcium bromide contains 20 g dm 3 What is the molarity of the solution with respect to calcium bromide and bromide ions? [Ca = 40, Br = 80] A. 1 B. 2 C. 05 D. 0.05, 0.1 |
B |
| 16. |
The substance ZnO dissolves in sodium hydroxide solution and mineral acid solution to give soluble products in each case. ZnO is therefore referred to as A. an allotropic oxide B. an amphoteric oxide C. a peroxide D. a dioxide |
B |
| 17. |
An acid and its conjugate base A. can neutralise each other to form a salt B. differ only by a proton C. differ only by the opposite charges they carry D. are always neutral substances |
B |
| 18. |
The same current is passed for the same time through solutions of AgNO3 and CuSO4 connected in series. How much silver will be deposited if 1.0 g of copper is produced? A. 1.7 g B. 3.4 g C. 8 g D. 6 g Detailed SolutionFrom Faraday;s second law of electrolysis\(\frac{\text{Mass of silver deposited}}{\text{Mass of copper deposited}}\) = \(\frac{\text{Equivalent mass of silver}}{\text{Equivalent mass of copper}}\) \(\frac{\text{Mass of silver deposited}}{1.0g}\) = \(\frac{108}{63.5}\) = 31.75g Copper is devalent = Cu2+ Mass of silver deposited = \(\frac{108g}{31.75g}\) = 3.30g |
|
| 19. |
What is discharged at the cathode during the electrolysis of copper (ll) tetraoxosulphate (VI) solution? A. Cu 2+ only B. H + only C. Cu 2+ and H D. Cu 2+ and SO 2- |
A |
| 20. |
An element, Z froms an anion whose formula is [Z(CN)6]y. If Z has an oxidation number of +2, what is the value of y? A. - 2 B. - 3 C. - 4 D. - 5 |
C |
| 11. |
The gaseous pollutant sulphur (IV)oxide is most likely to be detected in fairly reasonable quantities in the area around a plant for the A. extraction of aluminium from bauxite B. production of margarine C. smelting of copper D. production of chlorine from brine |
C |
| 12. |
Calcium hydroxide is added in the treatment of town water supply to A. kill bacteria in the water B. facilitate coagulation of organic particles C. facilitate sedimentation D. improve the taste of the water |
B |
| 13. |
A hydrated salt of formula MSO4.xH2 O CONTAINS 45.3% by mass of water of crystalisation. Calculate the value of x [M = 56, S = 32, O = 16, H = 1 ] A. 3 B. 5 C. 7 D. 10 |
C |
| 14. |
Using 50 cm 3 of 1 M potassium hydroxide and 100cm 3 of 1 M tetraoxosulphate (VI) acid, calculate the respective volumes in cm 3 of base and acid that would be required to produce the maximum amount of potassium tetraoxosulphate (IV) [ = 39, S = 32, O = 16, H = 1] A. 50, 50 B. 25, 50 C. 50, 25 D. 25, 25 |
C |
| 15. |
A solution of calcium bromide contains 20 g dm 3 What is the molarity of the solution with respect to calcium bromide and bromide ions? [Ca = 40, Br = 80] A. 1 B. 2 C. 05 D. 0.05, 0.1 |
B |
| 16. |
The substance ZnO dissolves in sodium hydroxide solution and mineral acid solution to give soluble products in each case. ZnO is therefore referred to as A. an allotropic oxide B. an amphoteric oxide C. a peroxide D. a dioxide |
B |
| 17. |
An acid and its conjugate base A. can neutralise each other to form a salt B. differ only by a proton C. differ only by the opposite charges they carry D. are always neutral substances |
B |
| 18. |
The same current is passed for the same time through solutions of AgNO3 and CuSO4 connected in series. How much silver will be deposited if 1.0 g of copper is produced? A. 1.7 g B. 3.4 g C. 8 g D. 6 g Detailed SolutionFrom Faraday;s second law of electrolysis\(\frac{\text{Mass of silver deposited}}{\text{Mass of copper deposited}}\) = \(\frac{\text{Equivalent mass of silver}}{\text{Equivalent mass of copper}}\) \(\frac{\text{Mass of silver deposited}}{1.0g}\) = \(\frac{108}{63.5}\) = 31.75g Copper is devalent = Cu2+ Mass of silver deposited = \(\frac{108g}{31.75g}\) = 3.30g |
|
| 19. |
What is discharged at the cathode during the electrolysis of copper (ll) tetraoxosulphate (VI) solution? A. Cu 2+ only B. H + only C. Cu 2+ and H D. Cu 2+ and SO 2- |
A |
| 20. |
An element, Z froms an anion whose formula is [Z(CN)6]y. If Z has an oxidation number of +2, what is the value of y? A. - 2 B. - 3 C. - 4 D. - 5 |
C |