Chemistry, 2002, JAMB Exam, Exam, Paper 1 | Objectives

Paper Info

Year :

2002

Title :

Chemistry

Exam :

JAMB Exam

Paper 1 | Objectives

11 - 20 of 47 Questions

#	Question	Ans
11.	When dissolved in water, NaOH flakes show A. An endothermic change B. An exothermic change C. A slow reaction D. A rapid reaction	B
12.	CU₂S_(s) + O_2(g) → 2CU_(s) + SO_2(g) What is the change in the oxidation number of copper in the reaction above? A. +1 to 0 B. 0 to +2 C. +2 to +1 D. 0 to +1	A
13.	The product of the electrolysis of dilute sodium hydroxide using platinum electrodes are A. Hydrogen and oxygen gases B. Water and hydrogen gas C. Water and sodium metal D. Sodium metal and oxygen gas	A
14.	The solubility of a salt of molar mass 101g at 20^oC is 0.34 mol dm^-3. If 3.40g of the salt is dissolved completely in 250cm³ of water in a beaker, the resulting solution is A. A suspension B. Saturated C. Unsaturated D. Supersaturated Show Content Detailed Solution At 20^oC 0.34 mol/dm of the salt dissolve = 0.34 * 101 = 34.34gm Of the salt dissolved. ∴ 34.34gm dissolve is 1,000cm³ If only 250 cm³ is the required mass X = (250/1000) * 34.34 = 8.555gm If only 3.40gm of the salt dissolved ,the solution is unsaturated	C
15.	Tetraoxosulphate (VI) acid burns the skin by A. Hydrolysis B. Hydration C. Heating D. Dehydration	D
16.	When a salt loses its water of crystallization to the atmosphere on exposure, the process is said to be A. Efflorescence B. Deliquescence C. Effervescence D. Fluorescence	A
17.	Three drops of a 1.0 mol dm^-3 solution of NaOH are added to 20 cm³ of a solution of pH 8.4. The pH of the resulting solution will be A. Close to that of pure water B. Unaltered C. Greater than 8.4 D. Less than 8.4	A
18.	25cm³ of a 0.2 mol dm³ solution of Na₂CO₃ requires 20 cm³ of a solution of HCl for neutralization. The concentration of the HCl solution is A. 0.5 mol dm³ B. 0.6 mol dm³ C. 0.2 mol dm³ D. 0.4 mol dm³	A
19.	The substance least considered as a source of environmental pollution is A. Lead compounds B. Organophosphorous compounds C. Silicate minerals D. Uranium	C
20.	The furring of kettles is caused by the presence in the water of A. Calcium tetraoxosulphate (VI) B. Calcium hydrogentrioxocarbonate (IV) C. Calcium hydroxide D. Calcium trioxocarbonate (IV) Show Content Detailed Solution In the presence of Calcium hydrogen trioxocarbonate(IV), a cause of temporary hardness of water, the kettle will most likely fur.	B

11.	When dissolved in water, NaOH flakes show A. An endothermic change B. An exothermic change C. A slow reaction D. A rapid reaction	B
12.	CU₂S_(s) + O_2(g) → 2CU_(s) + SO_2(g) What is the change in the oxidation number of copper in the reaction above? A. +1 to 0 B. 0 to +2 C. +2 to +1 D. 0 to +1	A
13.	The product of the electrolysis of dilute sodium hydroxide using platinum electrodes are A. Hydrogen and oxygen gases B. Water and hydrogen gas C. Water and sodium metal D. Sodium metal and oxygen gas	A
14.	The solubility of a salt of molar mass 101g at 20^oC is 0.34 mol dm^-3. If 3.40g of the salt is dissolved completely in 250cm³ of water in a beaker, the resulting solution is A. A suspension B. Saturated C. Unsaturated D. Supersaturated Show Content Detailed Solution At 20^oC 0.34 mol/dm of the salt dissolve = 0.34 * 101 = 34.34gm Of the salt dissolved. ∴ 34.34gm dissolve is 1,000cm³ If only 250 cm³ is the required mass X = (250/1000) * 34.34 = 8.555gm If only 3.40gm of the salt dissolved ,the solution is unsaturated	C
15.	Tetraoxosulphate (VI) acid burns the skin by A. Hydrolysis B. Hydration C. Heating D. Dehydration	D

16.	When a salt loses its water of crystallization to the atmosphere on exposure, the process is said to be A. Efflorescence B. Deliquescence C. Effervescence D. Fluorescence	A
17.	Three drops of a 1.0 mol dm^-3 solution of NaOH are added to 20 cm³ of a solution of pH 8.4. The pH of the resulting solution will be A. Close to that of pure water B. Unaltered C. Greater than 8.4 D. Less than 8.4	A
18.	25cm³ of a 0.2 mol dm³ solution of Na₂CO₃ requires 20 cm³ of a solution of HCl for neutralization. The concentration of the HCl solution is A. 0.5 mol dm³ B. 0.6 mol dm³ C. 0.2 mol dm³ D. 0.4 mol dm³	A
19.	The substance least considered as a source of environmental pollution is A. Lead compounds B. Organophosphorous compounds C. Silicate minerals D. Uranium	C
20.	The furring of kettles is caused by the presence in the water of A. Calcium tetraoxosulphate (VI) B. Calcium hydrogentrioxocarbonate (IV) C. Calcium hydroxide D. Calcium trioxocarbonate (IV) Show Content Detailed Solution In the presence of Calcium hydrogen trioxocarbonate(IV), a cause of temporary hardness of water, the kettle will most likely fur.	B