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Online Mock Tests
Chapters
2: Nutrition in Animals
3: Fibre to Fabric
4: Heat
5: Acids, Bases and Salts
▶ 6: Physical and Chemical Changes
7: Weather, Climate and Adaptation of Animals to Climate
8: Wind, Storm and Cyclone
9: Soil
10: Respiration in Organisms
11: Transportation in Animals and Plants
12: Reproduction in Plants
13: Motion and Time
14: Electric Current and Its Effects
15: Light
16: Water : A Precious Resource
17: Forests : Our Lifeline
18: Wastewater Story
![NCERT Exemplar solutions for Science [English] Class 7 chapter 6 - Physical and Chemical Changes - Shaalaa.com](/images/science-english-class-7_6:5f2b1b2038084cf381bfa42c826a928c.jpg "NCERT Exemplar solutions for Science [English] Class 7 chapter 6 - Physical and Chemical Changes")
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Solutions for Chapter 6: Physical and Chemical Changes
Below listed, you can find solutions for Chapter 6 of CBSE NCERT Exemplar for Science [English] Class 7.
NCERT Exemplar solutions for Science [English] Class 7 6 Physical and Chemical Changes MULTIPLE CHOICE QUESTIONS [Pages 33 - 34]
Which of the following is a physical change?
Rusting of iron
Combustion of magnesium ribbon
Burning of candle
Melting of wax
Which of the following is a chemical change?
Twinkling of stars
Cooking of vegetables
Cutting of fruits
Boiling of water
A chemical change may involve –
change in colour only
- change in temperature only
evolution of gas only
any or all of the above
Which of the following is/are true when milk changes into curd?
- Its state is changed from liquid to semi-solid.
- It changes colour.
- It changes the taste.
- The change cannot be reversed.
Choose the correct option from below:
(i) and (ii) are correct
(ii) and (iii) are correct
(i), (iii) and (iv) are correct
(i) to (iv) are correct
A man painted his main gate made up of iron, to
- prevent it from rusting.
- protect it from the sun.
- make it look beautiful.
- make it dust-free.
Which of the above statement(s) is/are correct?
(i) and (ii)
(ii) and (iii)
only (ii)
(i) and (iii)
The iron pillar near the Qutub Minar in Delhi is famous for the following facts. Which of these facts is responsible for its long stability?
It is more than 7 metres high.
It weighs about 6000 kg.
It was built more than 1600 years ago.
It has not rusted after such a long period.
Galvanisation is a process used to prevent the rusting of which the following?
Iron
Zinc
Aluminium
Copper
Paheli’s mother made a concentrated sugar syrup by dissolving sugar in hot water. On cooling, crystals of sugar got separated. This indicates a
a physical change that can be reversed.
the chemical change that can be reversed.
a physical change that cannot be reversed.
the chemical change that cannot be reversed.
Which of the following statement is incorrect for a chemical reaction?
Heat may be given out but never absorbed.
The sound may be produced.
A colour change may take place.
A gas may be evolved.
Two drops of dilute sulphuric acid were added to 1 g of copper sulphate powder and then a small amount of hot water was added to dissolve it (step I). On cooling, beautiful blue coloured crystals got separated (step II). Step I and Step II are:
physical and chemical changes respectively.
chemical and physical changes respectively.
both physical changes.
both chemicals change.
NCERT Exemplar solutions for Science [English] Class 7 6 Physical and Chemical Changes VERY SHORT ANSWER QUESTIONS [Pages 35 - 36]
State whether the following statements are true or false:
When a candle burns, both physical and chemical changes take place.
True
False
State whether the following statements are true or false:
Anaerobic bacteria digest animal waste and produce biogas.
True
False
State whether the following statements are true or false:
Ships suffer a lot of damage though they are painted.
True
False
State whether the following statements are true or false:
Stretching of rubber bands is not a physical change.
True
False
Melting of wax is a change where a solid changes to a liquid state. Give one more such change which you observe in your surroundings
What kind of change is shown by tearing off paper?
Match the items of Column I with the items of Column II
| Column 1 | Column II | ||
| (a) | Large crystals | (i) | Turns lime water into milky |
| (b) | Depositing a layer of zinc on iron | (ii) | Physical change |
| (c) | Souring of milk | (iii) | Rust |
| (d) | Carbon dioxide | (iv) | Sugar candy (Mishri) |
| (e) | Iron oxide | (v) | Chemical change |
| (f) | Dissolving common salt in water | (vi) | Galvanisation |
Fill in the blanks in the following statements using the words given in the box.
Making sugar solution is a ____________ change.
A physical change is generally____________.
Grinding of wheat grain changes its size. It is a ____________ change.
Iron benches kept in lawns and gardens get____________. It is a _________ change because a new _________ is formed.
Classify the following processes into physical or chemical changes:
(i) Beating of aluminium metal to make aluminium foil.
(ii) Digestion of food.
(iii) Cutting of a log of wood into pieces.
(iv) Burning of crackers.
Write word equations for two chemical reactions with the help of materials given in the box.
Air, copper sulphate, iron, vinegar, iron oxide, carbon dioxide, iron sulphate, copper, lime water, water
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Explain the following:
Bubbles are produced when acetic acid is added to a solution of sodium hydrogencarbonate.
NCERT Exemplar solutions for Science [English] Class 7 6 Physical and Chemical Changes LONG ANSWER QUESTIONS [Pages 36 - 37]
Give two examples for each of the following cases:
Physical changes are reversible.
Give two examples for each of the following cases:
Physical changes which are not reversible.
Give two examples for each of the following cases:
Chemical changes.
Give an example of a chemical reaction for each of the following situations:
A change in colour is observed.
Give an example of a chemical reaction for each of the following situations:
Gas is evolved.
Give an example of a chemical reaction for each of the following situations:
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 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.
Solutions for 6: Physical and Chemical Changes
NCERT Exemplar solutions for Science [English] Class 7 chapter 6 - Physical and Chemical Changes
Shaalaa.com has the CBSE Mathematics Science [English] Class 7 CBSE solutions in a manner that help students grasp basic concepts better and faster. The detailed, step-by-step solutions will help you understand the concepts better and clarify any confusion. NCERT Exemplar solutions for Mathematics Science [English] Class 7 CBSE 6 (Physical and Chemical Changes) include all questions with answers and detailed explanations. This will clear students' doubts about questions and improve their application skills while preparing for board exams.
Further, we at Shaalaa.com provide such solutions so students can prepare for written exams. NCERT Exemplar textbook solutions can be a core help for self-study and provide excellent self-help guidance for students.
Concepts covered in Science [English] Class 7 chapter 6 Physical and Chemical Changes are Classification of Change: Physical Changes, Chemical Reaction, Corrosion of Metals, Crystallisation Method, Experiment of Chemical Change.
Using NCERT Exemplar Science [English] Class 7 solutions Physical and Chemical Changes exercise by students is an easy way to prepare for the exams, as they involve solutions arranged chapter-wise and also page-wise. The questions involved in NCERT Exemplar Solutions are essential questions that can be asked in the final exam. Maximum CBSE Science [English] Class 7 students prefer NCERT Exemplar Textbook Solutions to score more in exams.
Get the free view of Chapter 6, Physical and Chemical Changes Science [English] Class 7 additional questions for Mathematics Science [English] Class 7 CBSE, and you can use Shaalaa.com to keep it handy for your exam preparation.
