Chemical combination - Jamb Chemistry Past Questions and Answers

Question 91:

• JAMB 1999

Use the table above to answer this question .The least reactive element is

A. W
B. X
C. Y
D. Z

Question 92:

• JAMB 2000

How many moles HCL will be required to react with potassium heptaoxodichromate (VI) to produce 3 moles of chlorine?

A. 14
B. 12
C. 11
D. 10

Question 93:

• JAMB 2000

The partial pressure of oxygen in a sample of air is 452 mm Hg and the total pressure is 780 mm Hg. What is the mole fraction of oxygen?

A. 0.203
B. 0.579
C. 2.030
D. 5.790

Question 94:

• JAMB 2001

25cm³ of a gas X contains Z molecules at 15^oC and 75 mmHg. How many molecules will 25 cm³ of another gas Y contain at the same temperature and pressure?

A. 2 Y
B. 2 Z
C. Z
D. Y

Question 95:

• JAMB 2001

What mass of water is produced when 8.0g of hydrogen reacts with excess oxygen?
[H = 1, O = 16]

A. 36.0g
B. 8.0g
C. 72.0g
D. 16.0g