Chemical combination - Jamb Chemistry Past Questions and Answers

Question 101:

• JAMB 2003

What volume of oxygen is produced from the decomposition of 2 mole of KCIO₃ at s.t.p?
[Molar volume of a gas at s.t.p = 22.4 dm³]

A. 22.4 dm³
B. 33.6 dm³
C. 44.8 dm³
D. 67.2 dm³

Question 102:

• JAMB 2003

What is the percentage by mass of oxygen in Al₂(SO₄)₃. 2H₂O?
[Al = 27, S = 32, H = 1, O = 16]

A. 14.29%
B. 25.39%
C. 50.79%
D. 59.25%

Question 103:

• JAMB 2003

What mass of K₂CrO₄ is required to prepare 250cm³ of 0.020 mol dm³ solution?
[K₂CrO₄ = 194.2g mol^-1]

A. 0.97g
B. 9.70g
C. 19.42g
D. 97.10g

Question 104:

• JAMB 2003

When 10g of sodium hydroxide is dissolved in 1000cm³ of water, the sodium formed is approximately
[Na = 23, H = 1, O = 16]

A. 0.01 mol dm^-3
B. 0.10 mol dm^-3
C. 0.25 mol dm^-3
D. 0.50 mol dm^-3

Question 105:

• JAMB 2004

If a solution contains 4.9g of tetraoxosulphate (VI) acid, calculate the amount of copper (II) oxide that will react with it
[Cu = 64, O = 16, S = 32, H = 1]

A. 0.8g
B. 4.0g
C. 40.0g
D. 80.0g