Chemistry Past Questions and Answers

If 48,000 coulombs of electricity are required to discharge 0.5 mole of sodium from a molten sodium chloride mass, then the number of coulombs required to discharge 2 moles of lead from molten lead (ll) chloride is?

A 48,000
B 96,000
C 192,000
D 384,000
E 576,000

Question 32:

The following compounds are given with their corresponding boiling points.
Compound Boiling Point
i.................................14°C
ii................................24°C
iii................................0°C
iv................................120°C
V.................................-2°C
From the above information, indicate which of the following is correct?

A All the compounds are gaseous at 20 Â°C
B One of the compounds is gaseous at 20 °C
C Two of the compounds are gaseous at 20 Â°C
D Three of the compounds are gaseous at 20 Â°C
E None of the compounds is gaseous at 20 Â°C

Question 33:

The products of the reaction between dilute sulphuric acid and sodium thiosulphate crystals are?

A Na₂SO₄ + SO₂ + O₂ + H₂O
B Na₂SO₃ + SO₃ + O₂ + H₂O
C Na₂SO₄ + SO₂ + S + H₂O
D Na₂SO₄ + SO₃ + S + H₂O
E Na₂SO₄ + SO₂ + H₂O only

Question 34:

Which of the following is NOT a true statement of the kinetic Theory of Gases?

A The molecules move at random
B The size of molecules is negligble as compared with the volume of gas
C The molecular collisions are perfectly elastic
D Every molecule has the same kinetic energy at a particular temperature
E The average kinetic energy is proportional to the absolute temperature of the gas

Question 35:

The electronic configuration of elements X and Y are X = 2, 8, 6; Y = 2, 8, 7. The bond in the compound formed by X and Y is expected to be?

A Ionic
B Covalent
C Dative covalent
D Metallic
E None of the above