NCERT Solutions for Chapter: Physical and Chemical Changes, Exercise 4: LONG ANSWER QUESTIONS
NCERT Science Solutions for Exercise - NCERT Solutions for Chapter: Physical and Chemical Changes, Exercise 4: LONG ANSWER QUESTIONS
Attempt the practice questions on Chapter 6: Physical and Chemical Changes, Exercise 4: LONG ANSWER QUESTIONS with hints and solutions to strengthen your understanding. NCERT Exemplar Science - Class 7 solutions are prepared by Experienced Embibe Experts.
Questions from NCERT Solutions for Chapter: Physical and Chemical Changes, Exercise 4: LONG ANSWER QUESTIONS with Hints & Solutions
Give an example of a chemical reaction for the following situation:
Sound is produced.
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust. Do you think rust is different from iron?
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.
Can you change rust back into iron by some simple method?
If you leave a piece of iron in the open for a few days, it acquires a film of a brownish substance called rust.
Do you think the formation of rust from iron is a chemical change?
If you leave a piece of iron in the open for a few days, it acquires a film of brownish substance, called rust.
Give two other examples of a similar type of change.
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
What changes do you expect?A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
Are these changes chemical in nature?A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
Write a word equation for the chemical change, if any.
