Chemistry 2018 Waec Past Questions and Answers

Question 21 :

• WAEC 2018

Stainless steel is an alloy comprising of

A. Fe and C
B. Fe and Ni
C. Fe, C and Ni
D. Fe, C and Al

Question 22 :

• WAEC 2018

The number of Hydrogen ions in 1.0\(dm^{3}\) of 0.02\(moldm^{-3}\) tetraoxosulphate(VI) acid is \([N_{A} = 6.02 \times 10^{23}]\)

A. \(1.2 \times 10^{22}\)
B. \(1.2 \times 10^{23}\)
C. \(2.4 \times 10^{22}\)
D. \(2.4 \times 10^{23}\)

Question 23 :

• WAEC 2018

The most suitable substance for putting out petrol fire is

A. Water
B. Carbon(IV) oxide
C. Fire blanket
D. Sand

Question 24 :

• WAEC 2018

The following factors would contribute to environmental pollution except

A. Production of ammonia
B. Manufacture of cement
C. Photosynthesis
D. Combustion

Question 25 :

• WAEC 2018

The position of equilibrium in a reversible reaction is affected by

A. Particle size of the reactants
B. Vigorous stirring of the reaction mixture
C. Presence of a catalyst
D. Change in concentration of the reactants