Question

(a) State the law of conservation of mass.

(b) What do you observe when barium chloride solution is mixed with sodium sulphate solution ?

Answer 1

Answer:
(a) “Matter can neither be created nor be destroyed in a chemical reaction”. However, it may change
from one form to another in the process.
It can also be stated as, “In a chemical reaction, the total mass of the reactants is equal to the total
mass of the products”.
(b)
We will observe that a white insoluble solid (precipitate) of barium sulphate is formed along with a
solution of sodium chloride. Wait for ten minutes to complete the reaction and the solid formed to
settle down.
Weigh the content again and note the reading.
We will observe that,
total mass of the apparatus + reactants = total mass of apparatus + products
Hence the law of conservation of mass is verified.