Jamb Chemistry Past Questions For Year 1991
Question 1
Which of the following can be obtained by fractional distillation?
- A. Nitrogen from liquid air
- B. Sodium chloride from sea water
- C. Iodine from a solution of Iondine in carbon tetrachloride
- D. Sulphur from a solution of sulphur incarbon disulphide
Question 2
Calculate the volume of carbon (IV)oxide measured at s.t.p, produced when 1 kg of potassium hydrogen trioxocarbonate (IV) is totally decomposed by heat?
(G.M.V. at s.t.p 22.4 dm3, K = 39, O = 16, C = 12, H = 1)
- A. 28 dm3
- B. 56 dm3
- C. 112 dm3
- D. 196 dm3
Question 3
30cm\(^3\) of oxygen at 10 atmospheres pressure is placed in a 20 cm\(^3\) container. Calculate the new pressure if temperature is kept constant?
- A. 6.7 atm
- B. 15.0 atm
- C. 60.0 atm
- D. 66. 0 atm
Question 4
In two separate experiments, 0.36g and 0.71g of chlorine combined with a metal X to give Y and Z respectively. An analysis showed that Y and Z contain 0.20g and 0.40g of X respectively. The data above represents the law of ?
- A. multiple proportion
- B. conservation of mass
- C. constant composition
- D. reciprocal proportion
Question 5
An iron ore is known to contain 70.0% Fe2O3. The obtain from 80kg of the ore is?
(Fe = 56, O = 16)
- A. 35.0 kg
- B. 39.2 kg
- C. 70.0 kg
- D. 78.4 kg
