ALKALIS

　

1. Ammonia solution can probably be found in

A. beer.
B. oven cleaner.
C. window cleaner.
D. soft drink.

　

2. Which of the following items is alkaline?

A. Lemon juice.
B. Hair conditioner.
C. Red wine.
D. Window cleaner.

　

3. When added to sodium hydroxide solution, phenolphthalein changes colour

	From	To
A.	Colourless	orange
B.	Colourless	pink
C.	Red	colourless
D.	Red	blue

　

4. When added to sodium hydroxide solution, methyl orange changes colour

	From	To
A.	Orange	yellow
B.	Orange	red
C.	Orange	blue
D.	Orange	purple

　

5. Caustic soda contains

A. potassium hydroxide

B. ammonia water

C. sodium carbonate

D. sodium hydroxide

　

6. Alkalis are

A. metal oxides and hydroxides only.

B. soluble bases.

C. insoluble bases.

D. sodium, potassium and calcium oxides and hydroxides only.

　

7. Alkalis have

A. bitter taste.

B. sour taste.

C. sweet taste.

D. salty taste.

　

8. Lime is added to soil to

A. remove weeds.

B. lower soil acidity.

C. kill bacteria.

D. fertilize the soil.

　

9. Sodium hydroxide is a strong alkali because

A. sodium is very reactive.

B. sodium hydroxide is very soluble in water.

C. sodium hydroxide reacts quickly with acids.

D. sodium hydroxide nearly completely ionizes when dissolves in water.

　

10. The elements listed below were burned in oxygen. The products were mixed with water. Which solution has a pH greater than 7 ?

A. Calcium

B. Carbon

C. Hydrogen

D. Phosphorus

　

11. Which of the following ions will mix with sodium hydroxide to form a clear solution?

A. Cu²⁺(aq)

B. Fe²⁺(aq)

C. Fe³⁺(aq)

D. K⁺(aq)

　

12. In which of the following cases will gas X produce an obvious change in the appearance of an aqueous solution of Y?

		X		Y
A.	Ammonia		Ethanoic acid
B.	Water vapour		Copper(II) sulphate
C.	Sulphur dioxide		Ammonia
D.	Carbon dioxide		Calcium hydroxide

　

13. Consider the following chemical equation:

NH₄Cl(aq) + KOH(aq) == KCl(x) + NH₃(y) + H₂O(z)

Which of the following combinations is correct?

	x	y	z
A.	aq	aq	aq
B.	aq	g	l
C.	l	g	aq
D.	l	aq	l

　

14. Which of the following substances will NOT react with sodium hydroxide solution?

A. Ammonium chloride solution

B. Citric acid

C. Lead(II) nitrate solution

D. Potassium chloride solution

　

15. Iron(II) chloride solution is mixed with chlorine water. Excess sodium hydroxide solution is then added to the mixture. The colour of the precipitate formed is

A. brown.

B. yellow.

C. green.

D. white.

　

16. The table shows the results of two tests on a substance X.

Test	Description	Observation
I	Warming X with sodium hydroxide solution.	A gas which turns moist red litmus paper blue is given off.
II	Mixing solution of X with silver nitrate solution.	A white precipitate forms.

X could be

A. ammonium chloride.

B. ammonium nitrate.

C. potassium chloride.

D. potassium nitrate.

　

17. A mixture consists of two solids, sodium chloride and lead(II) oxide. Which of the following methods can be used to remove the sodium chloride from the mixture?

A. Add water to the mixture and then filter.

B. Add dilute nitric acid to the mixture and then filter.

C. Add concentrated sulphuric acid to the mixture and then filter.

D. Add dilute hydrochloric acid to the mixture and then filter.

　

18. A wasp sting is alkaline. The solution to help ease the pain by neutralizing the alkali would be one with a pH value of

A. 1.

B. 4.

C. 8.

D. 10.

　

19. Sodium hydrogencarbonate can be found in

(1) baking powder.

(2) fizzy drink tablets.

(3) antiacid drugs.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

　

20. Which of the following reagents can be used to distinguish between Fe²⁺(aq) and Fe³⁺(aq) ions?

(1) Dilute sodium hydroxide solution

(2) Concentrated nitric acid

(3) Acidified potassium permanganate solution

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

　

21. Copper(II) oxide and carbon powder can be distinguished by

(1) heating each in excess air.

(2) heating each with lead(II) oxide.

(3) their appearance.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

　

22. Caesium is an element near the bottom of Group I of the periodic table. Which of the following statements about caesium are correct?

(1) Its hydroxide is a strong alkali.

(2) It reacts vigorously with water.

(3) It is liberated at the cathode during the electrolysis of caesium sulphate solution using carbon electrodes.

A. (1) and (2) only

B. (1) and (3) only

C. (2) and (3) only

D. (1), (2) and (3)

　

23. Ammonia is a weak alkali because

A. it is not very soluble in water.

B. it is a gas at room temperature and pressure.

C. it ionizes slightly in water.

D. it is not a metal hydroxide.

　

24. Dilute solutions of alkalis

A. are coloured.

B. have a strong, pungent odour.

C. have a slippery feel.

D. do not conduct electricity.

　

25. Some hazard warning labels are shown below:

Which of the labels should be shown on a bottle of dilute sodium hydroxide solution?

A.

B.

C.

D.

　

　

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