Jamb Chemistry 1999 Past Questions and Answers

Question 26:

• JAMB 1999

When a current I was passed through an electrolyte solution for 40 minutes, a mass X g of a univalent metal was deposited at the cathode. What mass of the metal will be deposited when a current 2I is passed through the solution for 10 minutes?

A. X/4 g
B. X/2 g
C. 2X g
D. 4X g

Question 27:

• JAMB 1999

RS_(aq) + HF_(aq) → RF_(s) + HS_(aq)
ΔH = -65.7 kj mol^(-1).
From the equation above, it can be deduced that

A. The heat content of the reactants is lower than that of the products
B. The heat content of the reactants is higher than that of the products
C. The reaction is slow
D. A large amount of heat is absorbed

Question 28:

• JAMB 1999

Which of the following statement is true of the electrochemical series?

A. Electropositivity of metals increase down the series
B. Electropositivity of non-metals decrease down the series
C. Electronegativity of non-metals decrease down the series
D. Electropositivity of metals decreases down the series

Question 29:

• JAMB 1999

The gas that will form a white precipitate with acidified silver trioxonitrate (v) is

A. NH₃
B. SO₂
C. CO₂
D. HCL

Question 30:

• JAMB 1999

Chlorine, bromine and iodine resemble one another in that they

A. Dissolve in alkalis
B. React violently with hydorgen without heating
C. Are liquids
D. Displace one another from solutiions of their salts