V K Sally and S K Aggarwal Solutions for Chapter: Physical and Chemical Changes, Exercise 2: EXERCISES
V K Sally Science Solutions for Exercise - V K Sally and S K Aggarwal Solutions for Chapter: Physical and Chemical Changes, Exercise 2: EXERCISES
Attempt the practice questions on Chapter 6: Physical and Chemical Changes, Exercise 2: EXERCISES with hints and solutions to strengthen your understanding. Learning Elementary Science for Class 7 solutions are prepared by Experienced Embibe Experts.
Questions from V K Sally and S K Aggarwal Solutions for Chapter: Physical and Chemical Changes, Exercise 2: EXERCISES with Hints & Solutions
Statement given below are incorrect. Write the correct statements.
Digestion of food is a physical change.
Statement given below are incorrect. Write the correct statements.
Magnetisation of steel is a chemical change.
Statement given below are incorrect. Write the correct statements.
Rusting can be stopped by adding metals like aluminium and copper to iron.
Statement given below are incorrect. Write the correct statements.
Crystallisation is the process used to make impure substances from pure substances.
Statement given below are incorrect. Write the correct statements.
Lime water turns milky in presence of carbon dioxide gas due to the formation of calcium sulphate.
Statement given below are incorrect. Write the correct statements.
The reaction between magnesium and oxygen produces heat and sound energy.
Identify both the physical and chemical changes which take place, when a candle is lighted.
Anita put a spoonful of common salt in a cup of water and stirred well. She poured this mixture in big plate and placed it in the sunlight for few hours. She observed common salt in the plate. She shared her observations with her science teacher, who explained changes involved in such process.
Answer the following questions based on above information:
(i) What are the values displayed by Anita?
(ii) What happens to common salt on stirring water?
(iii) Are the changes taking place in (i) and (ii) are reversible or irreversible? What scientific name is given to above changes?
