Question

Q1. Fill in the blanks-
[5]
i. No new substances are formed during a
change.
ii. Lead nitrate crystals on heating strongly leave behind a solid
residue, which is in
colour.
iii. When copper sulphide is treated with hydrochloric acid it gives
which has a foul smell.
iv. When quick lime is placed in water, an
reaction
takes place and the reaction mixture gets very hot.
v. The reaction between magnesium and oxygen is an -
reaction.
off a gas​

Answer 1

1. physical change

2. yellow

sorry i don't know 3 answer

4 . exothermic reaction

5.exothermic reaction

5 .