Question 286:

• JAMB 1982

Which of the following bonds exist in crystalline ammonium chloride (NH₄Cl)?

A. Ionic and covalent
B. Ionic and co-ordinate
C. Ionic covalent and co-ordinate
D. Covalent , co-ordinate and metalllic
E. Ionic, covalent and metallic

Question 287:

• JAMB 1982

When a pressure cooker is half filled with water, and heated to boiling point, then the pressure inside the cooker will?

A. Decrease, since only a fraction of the water molecules has changed to vapour
B. Remain constant, because the total number of water molecules has not changed
C. Increase, because the water molecules can now reach every part of the sealed tube
D. Decrease, since water boils under reduced pressure
E. Increase, because the water vapour molecules now strike the walls of the tube more frequently because of their increased velocity

Question 288:

• JAMB 1982

An element X has two isotopes, ²⁰₁₀X and ²⁰₁₀X,
present in the ratio 1:3. The relative atomic mass of X would be?

A. 20.5
B. 21.0
C. 21.5
D. 22.0
E. 22.5

Question 289:

• JAMB 1982

Which of the following is a neutralization reaction? Addition of

A. Nitric acid to hydrochloric acid
B. Nitric acid to sulphuric acid
C. Nitric acid to distilled water
D. Nitric acid to sodium hydroxide
E. Sodium chloride to distilled water

Question 290:

• JAMB 1982

A current of 10.0A was passed for 1 hour through a solution of copper (ll) sulphate between the copper electrodes. Which of the following observation would be correct?
(1 Faraday = 96,500 coulobms) (i) 0.186 mole of copper is dissolved from the anode. (ii) 0.372 mole of copper is deposited on the cathode. (iii) the original Cu²⁺ ion concentration of the solution remains unchanged. (iv) the original Cu²⁺ ion concentration of the solution decreases.

A. I and ii
B. I and iii
C. I and iv
D. Ii and iii
E. Ii and iv