NCERT Class VII Science Solutions: Chapter 5-Acids, Bases and Salts Part 1

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Question 1:

State differences between acids and bases.

Answer:

Difference between Acids and Bases
Difference between Acids and Bases

S.No

Acids

Bases

1.

Its taste is sour.

Its taste is bitter.

2.

When added to litmus solution, it turns red.

When added to litmus solution, it turns blue.

3.

Examples: Curd, lemon juice and vinegar.

Examples: Baking soda, Soap and lime water.

Diagram shows differences between acids and bases.

Differences between Acids and Bases

Diagram shows differences between acids and bases.

Question 2:

Ammonia is found in many household products, such as window cleaners. It turns red litmus blue. What is its nature?

Answer:

Bases turn red litmus blue, so nature of ammonia is basic.

As showing in images is a Ammonia

Ammonia

As showing in images is a Ammonia

Question 3:

Name the source from which litmus solution is obtained. What is the use of this solution?

Answer:

Litmus is extracted from lichens. It has a mauve (purple) colour in distilled water. When added to an acidic solution, it turns red and when added to a basic solution, it turns blue. So, it is used to test the acidic or basic nature of solutions.

As showing in images is a result for litmus solution is obtained

Result for Litmus Solution is Obtained

As showing in images is a result for litmus solution is obtained