MEDIUM
7th Kerala Board
IMPORTANT
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Can phenolphthalein be used as an indicator to distinguish between acid and alkali?

Important Questions on Acids and Alkalis

EASY
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 6>Q 1

See the table given below:

Question Image 

What are the substances that can be used as indicators to identify acid?
EASY
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 6>Q 2

See the table given below:

Question Image 

What are the indicators that can he used to identify alkali?
HARD
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 6>Q 3
What happens when dilute solutions of hydrochloric acid and caustic soda are mixed together?
HARD
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 7>Q 1
Why are indicators like phenolphthalein used while conducting neutralisation reactions?
HARD
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 7>Q 2
Soil in Kerala is generally acidic in nature. Do you understand why lime, which is alkaline, is added to soil?
EASY
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Exercise 8>Q 1

What are the advantages of making soap ourselves?

MEDIUM
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Let us assess>Q 1
The pH values of different soil samples are given in the option. Which of the soils should be treated with lime?
HARD
7th Kerala Board
IMPORTANT
Science for Class 7 - Part 1>Chapter 3 - Acids and Alkalis>Let us assess>Q 2
When a magician rubbed white paper with a handkerchief, red letters appeared on the paper. Which of the following materials might have been used by him?