Question

Chemical And Chemical Changes Class 7​

Answer 1

A
Iodine I
Silver Ag
Uranium U
Silicon Si

B
Sodium chloride
AlO2
Magnesium chloride

D
Both, burning of wick is chemical whereas melting of wax is physical (explain krke likhna thoda)

Answer 2

Answer:

A)match the following

1-c

2-e

3-a

4-b

B)

5-sodium chloride

6-Al2O3

7-Magnesium chloride

D)The process of burning (as opposed to evaporating) is a chemical reaction, a chemical change. The wax molecules are undergoing a chemical change; they are changing into different molecules by reacting with a substance in the air.

E)4Fe + 3O2 → 2Fe2O3.

iron+oxygen gives rust or iron oxide