Waec Chemistry 2013 Past Questions and Answers

Question 21:

• WAEC 2013

The volume of 0.25 moldm^-3 solution of KOH that would yield 6.5g of of solid KOH on evaporation is (K = 39.0; o = 16.0; H = 1.00)

A. 464.30 cm³
B. 625.00 cm³
C. 1000.00 cm³
D. 2153.80 cm³

Question 22:

• WAEC 2013

The percentage by mass of calcium in Ca(OCI)₂ is [Ca = 40.0; CI = 35.5; O = 16.0]

A. 28.0%
B. 31.6%
C. 43.8%
D. 44.5%

Question 23:

• WAEC 2013

The gas law which describes the relationship between volume and temperature is

A. Boyle's law
B. Charles' law
C. Dalton's law
D. Graham's law

Question 24:

• WAEC 2013

Which of the following phenomenna lead to decrease in volume of a liquid in an open container?

A. Brownian motion
B. Diffusion
C. Evaporation
D. Sublimation

Question 25:

• WAEC 2013

The pressure exerted by a gas is a function of the

A. Total volume of the gas
B. Speed of the gaseous molecules
C. Mass of each gaseous molecule
D. Frequency of collision between gaseous molecules