Chemistry, 2006, JAMB Exam, Exam, Paper 1 | Objectives

Paper Info

Year :

2006

Title :

Chemistry

Exam :

JAMB Exam

Paper 1 | Objectives

31 - 40 of 49 Questions

#	Question	Ans
31.	A decrease in atomic size and an increase in nuclear charge across a period lead to A. an increase in the tendency to lose electron B. an increase in chemical reactivity C. a decrease in electropositivity D. a decrease in covalency in bond formation	B
32.	The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is A. dissolution → dryness → filtration → evaporation B. filtration → sublimation → evaporation → dryness C. sublimation → dissolution → filtration → evaporation D. dissolution → filtration → sublimation → evaporation	C
33.	The idea of planetary electron was that of A. Rutherford B. Thompson C. Bohr D. Dalton	A
34.	If 30cm³ of gas at 50^oC is warmed to 80^o at a fixed pressure, the fractional increase in volume is A. 0.009 B. 0.093 C. 0.910 D. 1.090	D
35.	2C₂H_2(g) + 5O_2(g) → 4CO_2(g) + 2H₂O_(g) In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is [C =12, O = 16, H = 1] A. 264 g B. 39 g C. 352 g D. 156 g	A
36.	The ion that can be used as an oxidizing agent is A. Au³⁺ B. Fe³⁺ C. ClO^- D. Ca²⁺ Show Content Detailed Solution All the other options given, in their atom state can be good oxidizing agents but the ions are reducing agents.	C
37.	H_2(g) + Br_2(g) → 2HBr_(g) The above reaction is carried out at 25^oC. ΔH is -72 kJ mol^-1 and ΔS is - 106 J mol^-1K^-1, the reaction will A. not proceed spontaneously at the given B. proceed spontaneously at the given temperature C. proceed in the reverse direction at the given temperature D. proceed spontenously at lower temperature	A
38.	Zinc and carbon rods are used as anode and cathode respectively in a A. Leclanche cell B. lead accumulator C. Daniel cell D. voltaic cell Show Content Detailed Solution In a Leclanche cell, the anode and the cathode are a zinc rod and a carbon rod respectively. The electrolyte is an ammonium chloride solution or paste (wet or dry cell).	A
39.	The solution that will conduct the highest amount of electricity is? A. 0.5 mol dm^-3 of hydrochloric acid B. 2.0 mol dm^-3 of hydrochloric acid C. 0.5 mol dm^-3 ethanoic acid D. 2.0 mol dm^-3 ethanoic acid Show Content Detailed Solution Hence, for most aqueous solutions, the more ions, the higher the conductivity. Strong electrolytes ionize completely e.g strong acid, strong bases and some salts While weak electrolytes ionize only partially e.g CH3COOH is regarded as acetic acid. It is a weak electrolyte. Acetic acid is regarded as weak electrolyte because its dissociation constant is low.	B
40.	In which of the following is the oxidation number of sulphur equal to -2? A. SO₃ B. S₈ C. H₂S D. SO₂	C

31.	A decrease in atomic size and an increase in nuclear charge across a period lead to A. an increase in the tendency to lose electron B. an increase in chemical reactivity C. a decrease in electropositivity D. a decrease in covalency in bond formation	B
32.	The order in which a mixture of sand, ammonium chloride and sodium chloride can be separated is A. dissolution → dryness → filtration → evaporation B. filtration → sublimation → evaporation → dryness C. sublimation → dissolution → filtration → evaporation D. dissolution → filtration → sublimation → evaporation	C
33.	The idea of planetary electron was that of A. Rutherford B. Thompson C. Bohr D. Dalton	A
34.	If 30cm³ of gas at 50^oC is warmed to 80^o at a fixed pressure, the fractional increase in volume is A. 0.009 B. 0.093 C. 0.910 D. 1.090	D
35.	2C₂H_2(g) + 5O_2(g) → 4CO_2(g) + 2H₂O_(g) In the reaction above, the mass of carbon(IV)oxide produced on burning 78 g of ethyne is [C =12, O = 16, H = 1] A. 264 g B. 39 g C. 352 g D. 156 g	A

36.	The ion that can be used as an oxidizing agent is A. Au³⁺ B. Fe³⁺ C. ClO^- D. Ca²⁺ Show Content Detailed Solution All the other options given, in their atom state can be good oxidizing agents but the ions are reducing agents.	C
37.	H_2(g) + Br_2(g) → 2HBr_(g) The above reaction is carried out at 25^oC. ΔH is -72 kJ mol^-1 and ΔS is - 106 J mol^-1K^-1, the reaction will A. not proceed spontaneously at the given B. proceed spontaneously at the given temperature C. proceed in the reverse direction at the given temperature D. proceed spontenously at lower temperature	A
38.	Zinc and carbon rods are used as anode and cathode respectively in a A. Leclanche cell B. lead accumulator C. Daniel cell D. voltaic cell Show Content Detailed Solution In a Leclanche cell, the anode and the cathode are a zinc rod and a carbon rod respectively. The electrolyte is an ammonium chloride solution or paste (wet or dry cell).	A
39.	The solution that will conduct the highest amount of electricity is? A. 0.5 mol dm^-3 of hydrochloric acid B. 2.0 mol dm^-3 of hydrochloric acid C. 0.5 mol dm^-3 ethanoic acid D. 2.0 mol dm^-3 ethanoic acid Show Content Detailed Solution Hence, for most aqueous solutions, the more ions, the higher the conductivity. Strong electrolytes ionize completely e.g strong acid, strong bases and some salts While weak electrolytes ionize only partially e.g CH3COOH is regarded as acetic acid. It is a weak electrolyte. Acetic acid is regarded as weak electrolyte because its dissociation constant is low.	B
40.	In which of the following is the oxidation number of sulphur equal to -2? A. SO₃ B. S₈ C. H₂S D. SO₂	C