Practicing Class 7 Science MCQ and Class 7 Science Chapter 5 Changes Around Us Physical and Chemical MCQ Questions Online Test with Answers daily helps in time management.
Class 7 Changes Around Us Physical and Chemical MCQ with Answers
MCQ on Changes Around Us Physical and Chemical Class 7
Class 7 Science Chapter 5 Changes Around Us Physical and Chemical MCQ Questions with Answers
Question 1.
Change in state of matter is an example of ___________
(a) Physical change
(b) Chemical change
(c) Both physical and chemical change
(d) Combustion
Answer:
(a) Physical change
Question 2.
Weathering of rocks is an example of ___________
(a) Both physical and chemical changes
(b) Physical change
(c) Chemical change
(d) None of these
Answer:
(a) Both physical and chemical changes
Question 3.
Which of the following represents a chemical change?
(a) Rusting of iron foil
(b) Melting of glacier
(c) Crushing a peace of chalk into powder
(d) Folding sheets of papers to create new objects.
Answer:
(a) Rusting of iron foil
Question 4.
Which of the following is not an essential condition of combustion?
(a) Presence of oxygen
(b) Presence of combustible substance (Fuel).
(c) Ignition temperature
(d) Presence of carbon dioxide
Answer:
(d) Presence of carbon dioxide
Question 5.
Rust is chemically ___________
(a) Iron
(b) Iron oxide
(c) Iron chloride
(d) Iron hydroxide
Answer:
(b) Iron oxide
Changes Around Us Physical and Chemical Class 7 Assertion-Reason Type Questions
Assertion-Reason questions Directions: Each of the questions (i) and (ii) contain two statements – first ‘Assertion’ and second ‘Reason’. Select the correct answer to these questions from the codes (a), (b), (c) or (d) as given below:
(a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
(b) Both Assertion and Reason are true and Reason is NOT > the correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.
(i) Assertion (A): Baking soda reacts with vinegar, evolves oxygen gas.
Reason (R): It is a chemical change.
Answer:
(d) Assertion is false and Reason is true.
(ii) Assertion (A): Sediments formed, harden over time and become new rocks.
Reason (R): Most of these changes take place over few years and cannot be reversed.
Answer:
(c) Assertion is true and Reason is false.
Changes Around Us Physical and Chemical Class 7 Fill in the blanks
1. Fermentation of grapes is a ___________ change.
Answer:
Chemical change
2. Blowing air in tap water is a ___________ change.
Answer:
Physical change
3. New substances are formed through a process called ___________.
Answer:
Chemical reaction
4. Insoluble substance formed during a chemical reaction when C02 is passed through lime water, is ___________
Answer:
Calcium carbonate
5. A chemical reaction in which magnesium reacts with oxygen and produces heat and light along with white powder is called ___________
Answer:
Combustion
Changes Around Us Physical and Chemical Class 7 True or False
Question 1.
The component of air that supports combustion is Carbon dioxide.
Answer:
False
Explanation:
Correct word: Oxygen
Question 2.
We can test carbon dioxide gas by adding lime water to it.
Answer:
True
Question 3.
Some insects emit light in a field in late evenings, these insects are called Fireflies.
Answer:
True
Question 4.
Burning of candle is a physical change.
Answer:
False
Explanation:
Burning of a candle involves both Physical and Chemical changes)
Question 5.
The maximum temperature at which a substance catches fire is called its ignition temperature.
Answer:
False
Explanation:
Minimum Temperature
Changes Around Us Physical and Chemical Class 7 Match the following
Question 1.
Match the following items given in Column A with that in Column B:
| Column A | Column B |
| 1. Weathering | A. Physical change |
| 2. Condensation | B. Chemical change |
| 3. Landslide | C. Both physical and chemical changes |
| 4. Rancidity | D. Undesirable change |
Answer:
| Column A | Column B |
| 1. Weathering | C. Both physical and chemical changes |
| 2. Condensation | A. Physical change |
| 3. Landslide | D. Undesirable change |
| 4. Rancidity | B. Chemical change |