Chapter 1.2 Chemical equations

Question 1

What is the law of conservation of mass?

Answer 1

The total mass of the products formed in a reaction is equal to the total mass of the reactants.

Question 2

Balance these symbol equations:

a) KN03 => KNO2 + O2
b) Li + O2 => LI2O
c) Fe + O2 => Fe2O3
d) Fe2O3 + CO => Fe + CO2

Answer 2

a) 2KNO3 => 2KNO2 + O2
b) 4Li + O2 => 2Li2O
c) 4Fe + 3O2 => 2Fe2O3
d) Fe2O3 + 3CO => 2Fe + 3CO2

Question 3

What is the state symbol for solid, aqueous, liquid and gas?

Answer 3

Solid- (s), Liquid- (L), Aqueous- (aq) and gas- (g).