EASY
Earn 100

Write whether each of the following is a chemical change or a physical change:
Rusting of a nail.

85.71% studentsanswered this correctly

Important Questions on Changes Around Us

HARD
The gas we use in the kitchen is called liquefied petroleum gas (LPG). In the cylinder it exists as a liquid. When it comes out from the cylinder it becomes a gas (Change — A) then it burns (Change — B). The following statements pertain to these changes. Choose the correct one.
(i) Process — A is a chemical change.
(ii) Process — B is a chemical change.
(iii) Both processes A and B are chemical changes.
(iv) None of these processes is a chemical change.
MEDIUM
_____is a permanent change and it cannot be reversed.
MEDIUM
  Explain why, rusting of an iron objects are faster in coastal areas than in deserts?
HARD
Explain why rusting of iron objects is faster in coastal areas than in deserts.
HARD
Seed germination is an example of
MEDIUM
Why is germination of a seed a chemical change?
MEDIUM
Anaerobic bacteria digest animal waste and produce biogas (Change — A). The biogas is then burnt as fuel (Change — B). The following statements pertain to these changes. Choose the correct one.
(i) Process — A is a chemical change.
(ii) Process — B is a chemical change.
(iii) Both processes A and B are chemical changes.
(iv) None of these processes is a chemical change.
EASY

What type of change is curdling of milk?

EASY
 A change in which a new substance is formed is a _____ change.
MEDIUM
It protects us from harmful ultraviolet rays of the sun.
MEDIUM
How would you show that setting of curd is a chemical change?
EASY
Changes can sometimes result in new substances.
EASY

Give reasons: Burning of paper is a chemical change.

MEDIUM
Why are iron objects usually painted?
MEDIUM
 When a whisked egg is heated, it scrambles. Identify it is a physical or chemical change.
MEDIUM
When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it?