Changes Around Us Class 6 Worksheet Science

Q1: Multiple Choice Questions (MCQs)

(i) Which of the following is an example of a fast change?
(a) Aging of the human body
(b) Growth of a mango seedling
(c) Burning of paper
(d) Formation of coal
Ans: (c)
The burning of paper is a fast change, as it happens quickly when paper is set on fire.

(ii) What type of change is rusting of iron considered?
(a) Desirable change
(b) Reversible change
(c) Irreversible change
(d) Chemical change
Ans: (c)
Rusting of iron is an irreversible chemical change because it forms a different substance (iron oxide) that cannot be reversed.

(iii) Which of the following is an example of a reversible change?
(a) Water freezing into ice
(b) Cooking food
(c) Formation of salt solution
(d) Aging of the human body
Ans: (a)
Water freezing into ice is a reversible change because ice can be melted back into water.

(iv) What is the key difference between physical and chemical changes?
(a) Physical changes are always reversible, and chemical changes are not.
(b) Physical changes form new substances, while chemical changes do not.
(c) Physical changes affect the physical properties of a substance, while chemical changes involve a change in state.
(d) Physical changes involve the release of energy, while chemical changes use energy.
Ans: (b)
The main difference is that physical changes do not form new substances, whereas chemical changes do.

(v) Which of the following is a desirable change?
(a) Rotting of fruits
(b) Burning of paper
(c) Growth of plants from seeds
(d) Rusting of iron
Ans: (c)
The growth of plants from seeds is a desirable change as it benefits us by producing more plants.

Q2: Fill in the Blanks

(i) Water vapor changing back into water is an example of a ____________ change.
Ans: reversible

(ii) A change that affects only the physical properties of matter is called a ____________ change.
Ans: physical

(iii) Undesirable changes are those that are harmful or not ____________.
Ans: beneficial

(iv) The formation of crude oil, coal, and some rocks is an example of ____________ changes, which take millions of years.
Ans: slow

(v) When wood burns, it undergoes a ____________ change and produces heat and light energy.
Ans: chemical 

Q3: Match the Column (In a Table)

Match the items in Column A with their corresponding descriptions in Column B.
Ans:

Q4: True or False

(i) Desirable changes are harmful and not beneficial.
Ans: False
Desirable changes are beneficial and useful.

(ii) Reversible changes cannot be changed back to their original form.
Ans: False
Reversible changes can be changed back to their original form.

(iii) All chemical changes are irreversible changes.
Ans: True
Most chemical changes are irreversible, forming new substances.

(iv) The formation of coal from wood is a fast change.
Ans: False
The formation of coal from wood is an extremely slow change, taking millions of years.

(v) Physical changes always involve a change in the chemical composition of a substance.
Ans: False
Physical changes do not involve changes in the chemical composition; they affect only the physical properties of matter.