Jamb Chemistry 1999 Past Questions and Answers

Question 11:

• JAMB 1999

Nitrogen obtained from the liquefaction of air has a higher density than that obtained from nitrogen containing compounds because the former contains

A. Water vapour
B. Oxygen
C. Carbon (IV) oxide
D. Rare gases

Question 12:

• JAMB 1999

The method that can be used to convert hard water to soft water is

A. Chlorination
B. Passage over activated charcoal
C. The use of an ion-exchange resin
D. Aeration

Question 13:

• JAMB 1999

1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁷, 4s²
An element with the electronic configuration above is a

A. Non-metal
B. Metal
C. Transition element
D. Group two element

Question 14:

• JAMB 1999

Given that electronegativity increases across a period and decreases down a group in the periodic table, in which of the following compounds will the molecules be held together by the strongest hydrogen bond?

A. HF_(g)
B. NH_3(g)
C. CH_4(g)
D. HCl_(g)

Question 15:

• JAMB 1999

0.25 mole of hydrogen chloride was dissolved in distilled water and the volume made up of 0.50 dm³. If 15.0 cm³ of the solution requires 12.50 cm³ of aqueous sodium trioxocarbonate (IV) for neutralization, calculate the concentration of the alkaline solution

A. 0.30 mol dm³
B. 0.40 mol dm³
C. 0.50 mol dm³
D. 0.60 mol dm³