Jamb Chemistry Past Questions and Answers

Question 1551:

• JAMB 2010

Calculate the percentage by mass of nitrogen in calcium trioxonitrate (V)
[Ca = 40, N = 14, O = 16]

A. 8.5%
B. 13.1%
C. 17.1%
D. 27.6%

Question 1552:

• JAMB 2010

The droplets of water observed around a bottle of milk taken out of the refrigerator is due to the fact that the

A. Water vapour in the air around the bottle gains some energy from the bottle
B. Temperature of the milk drops as it loses heat into the surroundings
C. Saturated vapour pressure of the milk is equal to the atmospheric pressure
D. Water vapour in the air around the bottle loses some of its energy to the bottle

Question 1553:

• JAMB 2010

The volume of a given gas is V cm³P mm Hg. what is the new volume of the gas if the pressure is reduced to half at constant temperature

A. 4 V cm³
B. 2 V cm³
C. V/2 cm³
D. V cm³

Question 1554:

• JAMB 2010

Moving from left to right across a period, the general rise in the first ionization energy can be attributed to the

A. Decrease in nuclear charge
B. Increase in nuclear charge
C. Decrease in screening effect
D. Increase in screening effect

Question 1555:

• JAMB 2010

How many unpaired electron(s) are there in the nitrogen sub-levels/

A. 3
B. 2
C. 1
D. None