Year :
2014
Title :
Chemistry
Exam :
JAMB Exam
Paper 1 | Objectives
11 - 20 of 45 Questions
| # | Question | Ans |
|---|---|---|
| 11. |
Water is said to be temporarily hard when it contains A. Ca (HCO3)2 and Mg (HCO3)2 salts B. Ca (HCO3)2 and CaCO3 SALTS C. Mg(HCO3)2 and CaSO4 salts D. CaSO4 and Ca(HCO3)2 salts Detailed SolutionTemporary hardness is caused by the presence of dissolved calcium hydrogentrioxocarbonate(IV) which decomposes on heating to form calcium trioxocarbonate(IV).There is an explanation video available below. |
|
| 12. |
On exposure to the atmosphere, a hydrated salt loses its water of crystallization to become anhydrous. This phenomenon is referred to as A. efflorescence B. deliquescence C. hygroscopy D. hydrolysis |
|
| 13. |
16.55g of lead (ll) trioxonitrate (V) was dissolved in 100g of distilled water at 20oC, calculate the solubility of the solute in moldm-3 A. 0.05 g B. 2.00 g C. 1.00 g D. 0.50g Detailed Solutionmolar mass of pb (N0 3) 2 = 331Mole = \(\frac{16.55}{331}\)= 0.05 mole ∴0.05mole pb (No3)2 dissolved in 1000g H2O x = \(\frac{0.05\times1000}{100}\)= 0.5 mole /dm 3 There is an explanation video available below. |
|
| 14. |
The dispersion of a liquid in a liquid medium will give A. an emulsion B. a fog C. a gel D. an aerosol |
|
| 15. |
The major and most effective way of controlling pollution is to A. improve machinery so that the substances released from combustion are less harmful B. pass strict laws against it by individuals and companies C. educate people on the causes and effects of pollution D. convert chemical wastes to harmless substances before releasing them into the environment |
|
| 16. |
The basicity of CH3COOH is A. 4 B. 1 C. 2 D. 3 |
|
| 17. |
The colour of litmus in a neutral medium is A. purple B. pink C. yellow D. orange |
|
| 18. |
The mathematical expression of PH is A. log 10[OH-] B. log 101/[H 3 O+] C. log 10[H 3 O+] D. log 101/[OH -] |
|
| 19. |
Which of the following salts will turn blue litmus red? A. Sodium tetrahydroxozincate (ll) B. Sodium hydrogentetraoxosulphate (VI) C. Sodium trioxocarbonate (lV) D. Zinc chloride hydroxide |
|
| 20. |
Zn (s) + CuSO 4(aq) → ZnSO 4(aq) + Cu (s) A. 0 to + 4 B. 0 to + 2 C. + 1 to + 2 D. + 1 to + 3 |
| 11. |
Water is said to be temporarily hard when it contains A. Ca (HCO3)2 and Mg (HCO3)2 salts B. Ca (HCO3)2 and CaCO3 SALTS C. Mg(HCO3)2 and CaSO4 salts D. CaSO4 and Ca(HCO3)2 salts Detailed SolutionTemporary hardness is caused by the presence of dissolved calcium hydrogentrioxocarbonate(IV) which decomposes on heating to form calcium trioxocarbonate(IV).There is an explanation video available below. |
|
| 12. |
On exposure to the atmosphere, a hydrated salt loses its water of crystallization to become anhydrous. This phenomenon is referred to as A. efflorescence B. deliquescence C. hygroscopy D. hydrolysis |
|
| 13. |
16.55g of lead (ll) trioxonitrate (V) was dissolved in 100g of distilled water at 20oC, calculate the solubility of the solute in moldm-3 A. 0.05 g B. 2.00 g C. 1.00 g D. 0.50g Detailed Solutionmolar mass of pb (N0 3) 2 = 331Mole = \(\frac{16.55}{331}\)= 0.05 mole ∴0.05mole pb (No3)2 dissolved in 1000g H2O x = \(\frac{0.05\times1000}{100}\)= 0.5 mole /dm 3 There is an explanation video available below. |
|
| 14. |
The dispersion of a liquid in a liquid medium will give A. an emulsion B. a fog C. a gel D. an aerosol |
|
| 15. |
The major and most effective way of controlling pollution is to A. improve machinery so that the substances released from combustion are less harmful B. pass strict laws against it by individuals and companies C. educate people on the causes and effects of pollution D. convert chemical wastes to harmless substances before releasing them into the environment |
| 16. |
The basicity of CH3COOH is A. 4 B. 1 C. 2 D. 3 |
|
| 17. |
The colour of litmus in a neutral medium is A. purple B. pink C. yellow D. orange |
|
| 18. |
The mathematical expression of PH is A. log 10[OH-] B. log 101/[H 3 O+] C. log 10[H 3 O+] D. log 101/[OH -] |
|
| 19. |
Which of the following salts will turn blue litmus red? A. Sodium tetrahydroxozincate (ll) B. Sodium hydrogentetraoxosulphate (VI) C. Sodium trioxocarbonate (lV) D. Zinc chloride hydroxide |
|
| 20. |
Zn (s) + CuSO 4(aq) → ZnSO 4(aq) + Cu (s) A. 0 to + 4 B. 0 to + 2 C. + 1 to + 2 D. + 1 to + 3 |