Question

1 . Burning of coal is a type of Heaction

2.The chemical Reaction which produces heat is known as ----

a) Endothermic chemical reaction

b) Exothermic chemical reaction

c) Decomposition Reaction
d) Neutralisation reaction


3.Which One is the correct formula of “ Ammonium chloride”

4.We apply paint on iron articles because of-

a) Good looks
b) Prevention from sunlight
c) Prevention from
rusting


5.“Number of electrons present in the last shell. ” is known as
a) Atomic No.
b) Atomic Mass
c) Valency
d) Valence

electrons​

Answer 1

Answer:

1- Chemical reaction, Exothermic

2- Exothermic chemical reaction

3- NH4Cl

4- c) Paint acts as a coating and cuts off contact of iron with air to prevent rusting

5- C) Valence electrons

Answer 2

Answer:

1) It is a chemical reaction

2) b

3) alcl3

4) c

5) valency