Chemical combination - Jamb Chemistry Past Questions and Answers

Question 136:

• JAMB 2016

What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?
[Na=23, O=16, H=1]

A. 0.05 moldm^-3
B. 0.30 moldm^-3
C. 0.50 moldm^-3
D. 0.40 moldm^-3

Question 137:

• JAMB 2016

Calculate the volume in cm³ of oxygen evolved at s.t.p when a current of 5A is passed through acidified water for 193s?
[F = 96500 C mol¹. Molar volume of a gas at s.t.p = 22.4dm³]

A. 0.056dm³
B. 0.224dm³
C. 224.000dm³
D. 56.000dm³

Question 138:

• JAMB 2017

Calculate the amount in moles of a gas which occupies 10.5 dm³ at 6 atm and 30^oC [R = 082 atm dm³ K^-1 mol^-1]

A. 2.536
B. 1.623
C. 4.736
D. 0.394

Question 139:

• JAMB 2018

A given amount of gas occupies 10.0dm5 at 4atm and 273°C. The number of moles of the gas present is [Molar volume of gas at s.t.p = 22.4dm\(^3\)]

A. 0.89 mol
B. 1.90 mol
C. 3.80 mol
D. 5.70 mol

Question 140:

• JAMB 2018

A given amount of gas occupies 10.0dm5 at 4atm and 273°C. The number of moles of the gas present is [Molar volume of gas at s.t.p = 22.4dm\(^3\)]

A. 0.89 mol
B. 1.90 mol
C. 3.80 mol
D. 5.70 mol