Class 10 Science Chapter 2 MCQ

Class 10 Science Chapter 2 MCQ (Multiple Choice Questions) of Acids, Bases and Salts. All the MCQs are taken from NCERT Textbooks issued for session 2020-2021. Answers and explanation of MCQ tests are given just below each questions.

MCQs are important for the CBSE and other boards final exams. It also clears the concepts about Acids, Bases and salts. So, practice here with MCQ test and prepare for school exams and board exams.

Class 10 Science Chapter 2 MCQ with Answers

Class: 10 Science
Chapter: 2MCQ (Multiple Choice Questions) test

Class 10 Science Chapter 2 MCQ Test 2020-2021

CBSE Class 10 Science Chapter 2 MCQ tests with answer and complete explanation of each answer. MCQs are important for most of the boards like UP Board, Bihar Board, MP Board as well as CBSE board. So, prepare your chapter with the following 20 sets of MCQs containing about 100 questions.


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

[A]. H3O+ + Cl-
[B]. H3O+ + OH-
[C]. Cl- + OH-
[D]. Unionised HCl

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

[A]. Marble
[B]. Limestone
[C]. Baking soda
[D]. Lime

Consider the following statements and choose the correct statement(s):

[A]. Calcium carbonate reacts with dilute hydrochloric acid to form calcium chloride, carbon dioxide and water.
[B]. Calcium carbonate reacts with dilute sulphuric acid to form calcium sulphate, carbon dioxide and water.
[C]. When hydrochloric acid reacts with sodium hydroxide solution, then a neutralisation reaction takes place to form sodium chloride and water.
[D]. All the above

Which of the following gives the correct increasing order of acid strength?

[A]. Water < acetic acid < hydrochloride acid.
[B]. Water < hydrochloride acid < acetic acid.
[C]. Acetic acid < water < hydrochloride acid.
[D]. Hydrochloride acid < water < acetic acid.

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

[A]. Blue vitriol
[B]. Baking soda
[C]. Washing soda
[D]. Gypsum
Find the correct answer of MCQ

Consider the following statements and choose the incorrect one:

    • [A] The red cabbage extract is also a natural indicator.
    • [B] The red cabbage extract remains red in acidic solution, but turns green on adding two basic solution.
    • [C] Those substances whose smell changes in acidic or basic solution are called olfactory indicators.
    • [D] The smell of the onion cannot be detected when it is added to an acidic solution.

Explanation: Onion has a characteristic smell. An acidic solution like hydrochloric acid, does not destroy the smell of onions. When a basic solution like sodium hydroxide solution is added to a cloth strip treated with onions, then the onions smell cannot be detected.

Find the correct answer of MCQ

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

Explanation: Lemon juice is primarily a rich source of vitamin C which is citric acid.
Vinegar is a mixture of acetic acid and water. It is produced by acid acting bacteria. It is a mild acid.
Common salt is sodium chloride which has sodium ions and chloride ions. So, these three cannot change the pH paper to greenish blue as only base can bring this change.
Antacid is a base which is baking soda or sodium bicarbonate or sodium hydrogen carbonate which can change the pH paper from yellow orange to green while others are acidic in nature.

Calcium phosphate is present in tooth enamel. Its nature is [A] Basic [B] Acidic [C] Neutral [D] Amphoteric.

Explanation: Calcium phosphate Ca3(PO4)2 is basic salt, as it is formed by the combination of a weak acid (phosphoric acid) and slightly stronger base (calcium hydroxide). Bacteria feed on sugars commonly found in foods and produce acids in the mouth decreasing the pH level to 5.5 or lower. Thus, eroding the enamel that is basic in nature.

One of the constituents of baking powder is sodium hydrogen carbonate, the other constituent is [A] Hydrochloric acid [B] Tartaric acid [C] Acetic acid [D] Sulphuric acid

Explanation: Baking powder is a mixture of baking soda NaHCO3 (sodium hydrogen carbonate) and a mild edible acid such as tartaric acid. When baking powder is mixed with water, sodium hydrogen carbonate reacts with tartaric acid and accepts hydrogen ions from it. This process releases carbon dioxide gas which is trapped in the dough when baking powder is used to make bread and cake.

To protect tooth decay we are advised to brush our teeth regularly. The nature of toothpaste commonly used is [A] Acidic [B] Neutral [C] Basic [D] Corrosive

Explanation: Toothpastes we generally contain mild bases such as sodium fluoride or sodium bicarbonate in their composition. The base reacts with the acid formed during tooth decay and neutralises its bad effects thus, preventing tooth decay.
Note: When we eat food containing sugar, then the bacteria present in our mouth break down the sugar to form acids (such as lactic acid). Thus, acid is formed in the mouth after a sugary food has been eaten. This acid lowers the pH in the mouth (making it acidic). Tooth decay starts when the pH of acid formed in the mouth falls below 5.5.

Which of the following substances will not give carbon dioxide on treatment with dilute acid? [A] Marble [B] Limestone [C] Baking soda [D] Lime

Explanation: Lime (CaO) is the base that reacts with a dilute acid such as HCl to form a salt called “Calcium Chloride”. It is an exothermic reaction and releases water but no carbon dioxide. Mable or limestone (CaCO3) or baking soda (NaHCO3) react with HCl to release CO2.