NCERT Exemplar Solutions
Class 10 - Science - CHAPTER 2: Acids, Bases and Salts
Multiple Choice Questions

Choose the correct answer from the given four options:

Question.  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)

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Question.  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

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Question.  3

During the preparation of hydrogen chloride gas on a humid day, the gas is usually passed through the guard tube containing calcium chloride. What is the role of calcium chloride?

(a)

absorb the evolved gas

(b)

moisten the gas

(c)

absorb moisture from the gas

(d)

absorb Cl⁻ ions from the evolved gas

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Question.  4

Which of the following salts does not contain water of crystallisation?

(a)

Blue vitriol

(b)

Baking soda

(c)

Washing soda

(d)

Gypsum

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Question.  5

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

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Question.  6

Calcium phosphate is present in tooth enamel. Its nature is

(a)

basic

(b)

acidic

(c)

neutral

(d)

amphoteric

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Question.  7

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

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Question.  8

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

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Question.  9

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 apply solution of sodium hydroxide on the hand

(d)

Neutralise the acid with a strong alkali

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Question.  10

Sodium hydrogencarbonate when added to acetic acid evolves a gas. Which of the following statements are true about the gas evolved?

(i) It turns lime water milky

(ii) It extinguishes a burning splinter

(iii) It dissolves in a solution of sodium hydroxide

(iv) It has a pungent odour

(a)

(i) and (ii)

(b)

(i), (ii) and (iii)

(c)

(ii), (iii) and (iv)

(d)

(i) and (iv)

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Question.  11

Common salt besides being used in kitchen can also be used as the raw material for making

(i) washing soda

(ii) bleaching powder

(iii) baking soda

(iv) slaked lime

(a)

(i) and (ii)

(b)

(i), (ii) and (iv)

(c)

(i) and (iii)

(d)

(i), (iii) and (iv)

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Question.  12

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

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Question.  13

To protect tooth decay we are advised to brush our teeth regularly. The nature of the tooth paste commonly used is

(a)

acidic

(b)

neutral

(c)

basic

(d)

corrosive

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Question.  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

(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)

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Question.  15

The pH of the gastric juices released during digestion is

(a)

less than 7

(b)

more than 7

(c)

equal to 7

(d)

equal to 0

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Question.  16

Which of the following phenomena occur, when a small amount of acid is added to water?

(i) Ionisation

(ii) Neutralisation

(iii) Dilution

(iv) Salt formation

(a)

(i) and (ii)

(b)

(i) and (iii)

(c)

(ii) and (iii)

(d)

(ii) and (iv)

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Question.  17

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

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Question.  18

Which of the following substances will not give carbon dioxide on treatment with dilute acid?

(a)

Marble

(b)

Limestone

(c)

Baking soda

(d)

Lime

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Question.  19

Which of the following is acidic in nature?

(a)

Lime juice

(b)

Human blood

(c)

Lime water

(d)

Antacid

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Question.  20

In an attempt to demonstrate electrical conductivity through an electrolyte, the following apparatus was set up. Which among the following statement(s) is(are) correct?

(i) Bulb will not glow because electrolyte is not acidic

(ii) Bulb will glow because NaOH is a strong base 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

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Question.  21

Which of the following is used for dissolution of gold?

(a)

Hydrochloric acid

(b)

Sulphuric acid

(c)

Nitric acid

(d)

Aqua regia

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Question.  22

Which of the following is not a mineral acid?

(a)

Hydrochloric acid

(b)

Citric acid

(c)

Sulphuric acid

(d)

Nitric acid

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Question.  23

Which among the following is not a base?

(a)

NaOH

(b)

KOH

(c)

NH₄OH

(d)

C₂H₅OH

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Question.  24

Which of the following statements is not correct?

(a)

All metal carbonates react with acid to give a salt, water and carbon dioxide

(b)

All metal oxides react with water to give salt and acid

(c)

Some metals react with acids to give salt and hydrogen

(d)

Some non-metal oxides react with water to form an acid

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Question.  25

Match the chemical substances given in Column (A) with their appropriate application given in Column (B)

Column (A)Column (B)
(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)

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Question.  26

Equal volumes of hydrochloric acid and sodium hydroxide solutions of same concentration are mixed and the pH of the resulting solution is checked with a pH paper. What would be the colour obtained?

(a)

Red

(b)

Yellow

(c)

Yellowish green

(d)

Blue

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Question.  27

Which of the following is(are) true when HCl (g) is passed through water?

(i) It does not ionise in the solution as it is a covalent compound.

(ii) It ionises in the solution

(iii) It gives both hydrogen and hydroxyl ion in the solution

(iv) It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule

(a)

(i) only

(b)

(iii) only

(c)

(ii) and (iv)

(d)

(iii) and (iv)

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Question.  28

Which of the following statements is true for acids?

(a)

Bitter and change red litmus to blue

(b)

Sour and change red litmus to blue

(c)

Sour and change blue litmus to red

(d)

Bitter and change blue litmus to red

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Question.  29

Which of the following are present in a dilute aqueous solution of hydrochloric acid?

(a)

H₃O⁺ + Cl⁻

(b)

H₃O⁺ + OH⁻

(c)

Cl⁻ + OH⁻

(d)

unionised HCl

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Question.  30

Identify the correct representation of reaction occurring during chloralkali process

(a)

2NaCl(l) + 2H₂O(l) → 2NaOH(l) + Cl₂(g) + H₂(g)

(b)

2NaCl(aq) + 2H₂O(aq) → 2NaOH(aq) + Cl₂(g) + H₂(g)

(c)

2NaCl(aq) + 2H₂O(l) → 2NaOH(aq) + Cl₂(aq) + H₂(aq)

(d)

2NaCl (aq) + 2H₂O (l) → 2NaOH (aq) + Cl₂(g) + H₂(g)

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