Explain the changes occurring in burning of candle.

Important Questions on Physical and Chemical Changes

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.1>Q IV

Give two changes that are harmful. Explain why you consider them harmful. How can you prevent them?

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

What is rust? What is the formula of rust?

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

How can we prevent rusting of iron? Write any two ways.

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

What is crystallisation?

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

How does the painting of an iron gate prevent it from rusting?

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

What are the essential condition for rusting of iron?

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

Name any three salts present in sea water.

MEDIUM

7th CBSE

IMPORTANT

Exam Guru Science>Chapter 6 - Physical and Chemical Changes>Exercise 6.2>Q I

Name the brown flab substance formed on iron articles when exposed to moist air.