WAEC Chemistry questions

357 questions with answers and explanations. Tap an option to check yourself.

All topics Acids, bases and salts · 26 Air · 16 Atomic structure and bonding · 26 Chemical combination · 27 Chemical equilibrium · 16 Chemistry and industry · 17 Electrolysis · 19 Energy changes · 16 Environmental pollution · 15 Kinetic theory of matter and gas laws · 18 Metals and their compounds · 23 Non-metals and their compounds · 22 Organic compounds · 29 Oxidation and reduction · 19 Rates of chemical reaction · 16 Separation of mixtures and purification · 18 Solubility · 16 Water · 18

Question 321· Separation of mixtures and purification· WAEC
Kerosene and water poured into one container form two layers. Which apparatus separates them most simply?
Show answer
Answer: D. separating funnel
Explanation and discussion
Question 322· Separation of mixtures and purification· WAEC
Which method is best for separating a mixture of ethanol and water?
Show answer
Answer: B. fractional distillation
Explanation and discussion
Question 323· Separation of mixtures and purification· WAEC
In paper chromatography, the component that travels furthest is the one that is
Show answer
Answer: C. most soluble in the solvent and least attracted to the paper
Explanation and discussion
Question 324· Solubility· WAEC
A solution that can dissolve no more solute at a given temperature is said to be
Show answer
Answer: C. saturated
Explanation and discussion
Question 325· Solubility· WAEC
A solution in which more solute can still dissolve at that temperature is
Show answer
Answer: A. unsaturated
Explanation and discussion
Question 326· Solubility· WAEC
Particles in a colloid differ from those in a true solution in that they
Show answer
Answer: C. scatter light (the Tyndall effect)
Explanation and discussion
Question 327· Solubility· WAEC
The solubility of most gases in water
Show answer
Answer: D. decreases as temperature rises
Explanation and discussion
Question 328· Solubility· WAEC
Fish in a shallow pond may die on a very hot afternoon mainly because
Show answer
Answer: D. less oxygen dissolves in warm water
Explanation and discussion
Question 329· Solubility· WAEC
The solubility of KCl at 30 °C is 37 g per 100 g of water. What mass of KCl saturates 200 g of water at 30 °C?
Show answer
Answer: C. 74 g
Explanation and discussion
Question 330· Solubility· WAEC
The solubility of a salt is 30 g per 100 g of water at 25 °C. The mass that dissolves in 250 g of water is
Show answer
Answer: B. 75 g
Explanation and discussion
Question 331· Solubility· WAEC
Crystals form when a hot saturated solution of potassium trioxonitrate(V) is cooled because
Show answer
Answer: A. its solubility falls as the temperature falls
Explanation and discussion
Question 332· Solubility· WAEC
Which of these is a suspension?
Show answer
Answer: B. muddy water
Explanation and discussion
Question 333· Solubility· WAEC
Undissolved sugar remains at the bottom of a cup of tea after long stirring at a fixed temperature. The tea is
Show answer
Answer: A. saturated with sugar
Explanation and discussion
Question 334· Solubility· WAEC
Mayonnaise, made by shaking oil with egg and vinegar, is an example of
Show answer
Answer: C. an emulsion
Explanation and discussion
Question 335· Solubility· WAEC
Which gas is most soluble in water at room temperature?
Show answer
Answer: B. ammonia
Explanation and discussion
Question 336· Solubility· WAEC
A solution containing more solute than it can normally hold at that temperature is
Show answer
Answer: C. supersaturated
Explanation and discussion
Question 337· Solubility· WAEC
A solubility curve shows
Show answer
Answer: D. how the solubility of a substance changes with temperature
Explanation and discussion
Question 338· Solubility· WAEC
The solubility of a salt is 36 g per 100 g of water at 25 °C. What mass of it dissolves in 250 g of water at that temperature?
Show answer
Answer: A. 90 g
Explanation and discussion
Question 339· Solubility· WAEC
20 g of a salt dissolves in 50 g of water at 30 °C. Its solubility at 30 °C, in grams per 100 g of water, is
Show answer
Answer: C. 40 g
Explanation and discussion
Question 340· Water· WAEC
A deliquescent substance
Show answer
Answer: A. absorbs water from the air and dissolves in it
Explanation and discussion

Practise Chemistry like the real exam. A timed CBT, your score, and the topics to fix.

Start a Chemistry test

WAEC Chemistry questions

Kerosene and water poured into one container form two layers. Which apparatus separates them most simply?

Which method is best for separating a mixture of ethanol and water?

In paper chromatography, the component that travels furthest is the one that is

A solution that can dissolve no more solute at a given temperature is said to be

A solution in which more solute can still dissolve at that temperature is

Particles in a colloid differ from those in a true solution in that they

The solubility of most gases in water

Fish in a shallow pond may die on a very hot afternoon mainly because

The solubility of KCl at 30 °C is 37 g per 100 g of water. What mass of KCl saturates 200 g of water at 30 °C?

The solubility of a salt is 30 g per 100 g of water at 25 °C. The mass that dissolves in 250 g of water is

Crystals form when a hot saturated solution of potassium trioxonitrate(V) is cooled because

Which of these is a suspension?

Undissolved sugar remains at the bottom of a cup of tea after long stirring at a fixed temperature. The tea is

Mayonnaise, made by shaking oil with egg and vinegar, is an example of

Which gas is most soluble in water at room temperature?

A solution containing more solute than it can normally hold at that temperature is

A solubility curve shows

The solubility of a salt is 36 g per 100 g of water at 25 °C. What mass of it dissolves in 250 g of water at that temperature?

20 g of a salt dissolves in 50 g of water at 30 °C. Its solubility at 30 °C, in grams per 100 g of water, is

A deliquescent substance