Acids,Bases and Salts
Class 10th Science Chapter MCQs
Acids, Bases and Salts Class 10 MCQs Questions
1.
What happens when a solution of an acid is mixed with a
solution of a base in a test tube?
(i) The temperature of the solution
increases
(ii) The temperature of the solution decreases
(iii) The
temperature of the solution remains the same
(iv) Salt formation takes
place
(a) (i) only
(b) (i) and (iii)
(c) (ii) and (iii)
(d) (i) and
(iv)
Answer
Answer: (d) (i) and (iv)
2.
An aqueous solution turns red litmus solution blue. Excess
addition of which of the following solution would reverse the change?
(a)
Baking powder
(b) Lime
(c) Ammonium hydroxide solution
(d) Hydrochloric
acid
Answer
Answer: (d) Hydrochloric acid
3. When hydrogen chloride gas is prepared on a humid day, the gas is usually
passed through the guard tube containing calcium chloride. The role of calcium
chloride taken in the guard tube is to
(a) absorb the evolved gas
(b)
moisten the gas
(c) absorb moisture from the gas
(d) absorb Cl–
ions from the evolved gas
Answer
Answer: c
Explaination: Reason: Guard tube drys (absorbs water) from
calcium chloride on a humid day.
4. Which one of the following salts does not con-tain water of
crystallisation?
(a) Blue vitriol
(b) Baking soda
(c) Washing soda
(d) Gypsum
Answer
Answer: b
5. In terms of acidic strength, which one of the following is in the correct
increasing order?
(a) Water < Acetic acid < Hydrochloric acid
(b)
Water < Hydrochloric acid < Acetic acid
(c) Acetic acid < Water <
Hydrochloric acid
(d) Hydrochloric acid < Water < Acetic
acid
Answer
Answer: a
6. What is formed when zinc reacts with sodium hydroxide?
(a) Zinc
hydroxide and sodium
(b) Sodium zincate and hydrogen gas
(c) Sodium
zinc-oxide and hydrogen gas
(d) Sodium zincate and
water
Answer
Answer: b
Explaination: Reason: Zn + 2NaOH → Ma2Zn02
(Sodium Zincate) + H2
7. Tomato is a natural source of which acid?
(a) Acetic acid
(b) Citric
acid
(c) Tartaric acid
(d) Oxalic acid
Answer
Answer: d
8. Brine is an
(a) aqueous solution of sodium hydroxide
(b) aqueous
solution of sodium carbonate
(c) aqueous solution of sodium chloride
(d)
aqueous solution of sodium bicarbonate
Answer
Answer: c
9. Na2CO3 .
10H2O is
(a) washing soda
(b) baking soda
(c)
bleaching powder
(d) tartaric acid
Answer
Answer: a
10. At what temperature is gypsum heated to form Plaster of Paris?
(a)
90°C
(b) 100°C
(c) 110°C
(d) 120°C
Answer
Answer: b
11. How many water molecules does hydrated cal-cium sulphate contain?
(a)
5
(b) 10
(c) 7
(d) 2
Answer
Answer: d
Explaination: Reason: Chemical formula of hydrated calcium
sulphate or gypsum is CaSO4.2H2O
12. Sodium carbonate is a basic salt because it is a salt of a
(a) strong
acid and strong base
(b) weak acid and weak base
(c) strong acid and weak
base
(d) weak acid and strong base
Answer
Answer: d
13. Alkalis are
(a) acids, which are soluble in water
(b) acids, which
are insoluble in water
(c) bases, which are insoluble in water
(d) bases,
which are soluble in water
Answer
Answer: d
14. Which of the following statements is correct about an aqueous solution of
an acid and of a base?
(i) Higher the pH, stronger the acid
(ii) Higher
the pH, weaker the acid
(in) Lower the pH, stronger the base
(iv) Lower
the pH, weaker the base
(a) (i) and (iii)
(b) (ii) and (iii)
(c) (i)
and (iv)
(d) (ii) and (iv)
Answer
Answer: d
Explaination: Reason: Stronger the acid, lesser is the pH.
Stronger the base, higher is the pH.
15. The apparatus given in the adjoining figure was set up to demonstrate
electrical conductivity.
Which of the following statement(s) is (are) correct?
(i)
Bulb will not glow because electrolyte is not acidic.
(ii) Bulb will glow
because HCl is a strong acid and furnishes ions for conduction.
(iii) Bulb
will not glow because circuit is incomplete.
(iv) Bulb will not glow because
it depends upon the type of electrolytic solution.
(a) (i) and (iii)
(b)
(ii) and (iv)
(c) (ii) only
(d) (iv)
only
Answer
Answer: c
16. Lime water reacts with chlorine to give
(a) bleaching powder
(b)
baking powder
(c) baking soda
(d) washing
soda
Answer
Answer: c
Explaination:
17. Nettle sting is a natural source of which acid?
(a) MetiWanoic
acid
(b) Lactic acid
(c) Citric acid
(d) Tartaric
acid
Answer
Answer: a
18. Tooth enamel is made up of
(a) calcium phosphate
(b) calcium
carbonate
(c) calcium oxide
(d)
potassium
Answer
Answer: a
19. What is the pH range of our body?
(a) 7.0 – 7.8
(b) 7.2 – 8.0
(c) 7.0 – 8.4
(d) 7.2 – 8.4
Answer
Answer: a
20. Rain is called acid rain when its:
(a) pH falls below 7
(b) pH
falls below 6
(c) pH falls below 5.6
(d) pH is above
7
Answer
Answer: c
21. Sodium hydroxide is a
(a) weak base
(b) weak acid
(c) strong
base
(d) strong acid
Answer
Answer: c
Explaination: Reason: Sodium hydroxide ionises in water and
produces a large amount of hydroxide ions.
22. An aqueous solution turns red litmus solution blue. Excess addition of
which of the following solution would reverse the change?
(a) Baking
powder
(b) Lime
(c) Ammonium hydroxide solution
(d) Hydrochloric
acid
Answer
Answer: d
23. When copper oxide and dilute hydrochloric acid react, colour changes
to
(a) white
(b) bluish-green
(c) blue-black
(d)
black
Answer
Answer: b
Explaination: Reason: Blue-green colour of solution is due to
the formation of copper (II) chloride.
24. Sodium hydroxide is used
(a) as an antacid
(b) in manufacture of
soap
(c) as a cleansing agent
(d) in alkaline
batteries
Answer
Answer: b
25. Sodium hydroxide turns phenolphthalein solution
(a) pink
(b)
yellow
(c) colourless
(d) orange
Answer
Answer: a
26. Chemical formula of washing soda is
(a) Na2C03 .
7H2O
(b) Na2C03 . 5H2O
(c)
Na2C03 . 2H2O
(d)
Na2C03 .
10H2O
Answer
Answer: d
27.
Two aqueous solutions P and Q have pH of 5 and 13
respectively. The correct inference is that:
(a) solution P is of HCl and Q
is of NH4OH
(b) solution P is of CH3COOH and Q is of
Ca(OH)2
(c) solution P is of HNO3 and Q is of
NH4OH
(d) solution P is of CH3COOH and Q is of
NaOH
Answer
Answer: (d) solution P is of CH3COOH and Q is of NaOH
28.
The pH of a solution is 7. How can you increase its pH?
(a)
By adding a small amount of acid
(b) By adding a small amount of base.
(c)
By adding a small amount of salt.
(d) By passing carbon dioxide gas through
it.
Answer
Answer: (b) By adding a small amount of base.
29.
Sodium carbonate is a basic salt because it is a salt of
(a) strong acid and strong base
(b) weak acid and weak base
(c) strong
acid and weak base
(d) weak acid and strong base
Answer
Answer: (d) weak acid and strong base
30.
Which gas is evolved when acids react with metals?
(a)
O2
(b) CO2
(c) H2
(d)
N2
Answer
Answer: (c) H2
31.
A sample of soil is mixed with water and allowed to settle.
The clear supernatant solution turns the pH paper yellowish-orange. Which of the
following would change the colour of this pH paper to greenish- blue?
(a)
Lemon juice
(b) Vinegar
(c) Common salt
(d) An
antacid
Answer
Answer: (d) An antacid
32.
Which of the following gives the correct increasing order of
acidic strength?
(a) Water < Acetic acid < Hydrochloric acid
(b)
Water < Hydrochloric acid < Acetic acid
(c) Acetic acid < Water <
Hydrochloric acid
(d) Hydrochloric acid < Water < Acetic
acid
Answer
Answer: (a) Water < Acetic acid < Hydrochloric acid
33.
If a few drops of a concentrated acid accidentally spills over
the hand of a student, what should be done?
(a) Wash the hand with saline
solution.
(b) Wash the hand immediately with plenty of water and apply a
paste of sodium hydrogencarbonate.
(c) After washing with plenty of water and
apply solution of sodium hydroxide on the hand.
(d) Neutralise the acid with
a strong alkali.
Answer
Answer: (b) Wash the hand immediately with plenty of water and apply a paste of sodium hydrogencarbonate.
34.
Farmers neutralise the effect of acidity of the soil by
adding
(a) slaked lime
(b) gypsum
(c) caustic soda
(d) baking
soda
Answer
Answer: (a) slaked lime
35.
A teacher gave two test tubes to the students, one containing
water and the other containing sodium hydroxide. She asked them to identify the
test tube containing sodium hydroxide solution. Which one of the following can
be used for the identification?
(a) Blue litmus
(b) Red litmus
(c)
Sodium carbonate solution
(d) Dilute hydrochloric
acid
Answer
Answer: (b) Red litmus
36.
One of the constituents of baking powder is sodium
hydrogencarbonate, the other constituent is
(a) hydrochloric acid
(b)
tartaric acid
(c) acetic acid
(d) sulphuric
acid
Answer
Answer: (b) tartaric acid
37.
Increase in the OH– ion concentration, leads
to
(a) an increases in the pH of solution
(b) a decrease in the pH of the
solution
(c) doesn’t alter the pH of the solution
(d) decreases the basic
strength of the solution
Answer
Answer: (a) an increases in the pH of solution
38.
Which of the following statements is correct about an aqueous
solution of an acid and of a base?
(i) Higher the pH, stronger the acid
(ii) Higher the pH, weaker the acid
(iii) Lower the pH, stronger the base
(iv) Lower the pH, weaker the base
(a) (i) and (iii)
(b) (ii) and
(iii)
(c) (i) and (iv)
(d) (ii) and (iv)
Answer
Answer: (iv) Lower the pH, weaker the base
39.
A solution has turned the colour of red litmus paper to blue.
The pH of the solution is approximately:
(a) 2
(b) 5
(c) 7
(d)
10
Answer
Answer: (d) 10
40.
The pH of three solutions X, Y and Z is 6, 4 and 8
respectively. Which of the following is the correct order of acidic
strength?
(a) X > Y > Z
(b) Z > Y > X
(c) Y > X >
Z
(d) Z > X > Y
Answer
Answer: (c) Y > X > Z
41.
Which one of the following can be used as an acid-base
indicator by a visually impaired student?
(a) Litmus
(b) Turmeric
(c)
Vanilla essence
(d) Petunia leaves
Answer
Answer: (c) Vanilla essence
42.
What is gastric acid present in the stomach composed of?
(a) Hydrochloric acid
(b) Sulphuric acid
(c) Nitric acid
(d) Lactic
acid
Answer
Answer: (a) Hydrochloric acid
43.
Which of the following is acidic in nature?
(a) Lime
juice
(b) Human blood
(c) Lime water
(d)
Antacid
Answer
Answer: (a) Lime juice
44.
When the solution of an acid is diluted, what will be the
change in pH of the solution?
(a) pH of the solution remains the same
(b)
pH of the solution will increase
(c) pH of the solution decreases
(d) pH
of the solution climbs to 7
Answer
Answer: (a) pH of the solution remains the same
45.
When the stopper of a bottle containing colourless liquid was
removed, the bottle gave a smell like that of vinegar. The liquid in the bottle
could be
(a) Hydrochloric acid solution
(b) Sodium hydroxide solution
(c) Acetic acid solution
(d) Saturated sodium bicarbonate
solution
Answer
Answer: (a) Hydrochloric acid solution
46.
Which of the following is not a mineral acid?
(a)
Hydrochloric acid
(b) Citric acid
(c) Sulphuric acid
(d) Nitric
acid
Answer
Answer: (b) Citric acid
47.
Which among the following is not a base?
(a) NaOH
(b)
KOH
(c) NH4OH
(d)
C2H5OH
Answer
Answer: (d) C2H5OH
48.
To protect tooth decay, one is advised to brush the teeth
regulary. The ingredient of the paste which checks tooth decay is:
(a)
acidic
(b) basic
(c) neutral
(d) corrosive
Answer
Answer: (b) basic
49.
Match the chemical substances given in Column (A) with their
appropriate application given in Column (B).
| Column I | Column II |
| (A) Bleaching powder | (i) Preparation of glass |
| (B) Baking soda | (ii) Production of H2 and Cl2 |
| (C)Washing soda | (iii) Decolourisation |
| (D) Sodium chloride | (iv) Antacid |
(a) A-(ii), B-(i), C-(iv), D-(iii)
(b) A-(iii), B-(ii), C-(iv), D-(i)
(c) A-(iii), B-(iv), C-(i), D-(ii)
(d) A-(ii), B-(iv), C-(i),
D-(iii)
Answer
Answer: (c) A-(iii), B-(iv), C-(i), D-(ii)