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.


Difference between Acids and Bases





Its taste is sour.

Its taste is bitter.


When added to litmus solution, it turns red.

When added to litmus solution, it turns blue.


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

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Question 2:

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


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

As showing in images is a Ammonia


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Question 3:

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


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 obta …

Result for Litmus Solution is Obtained

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