Answer:-
103.168 grams
Explanation:-
When a hydrate salt is heated water is released and anhydrous salt is formed.
The balanced Chemical equation for the reaction is
MgCO3.3H2O --> MgCO3 + 3H2O
Molecular mass of MgCO3.3H2O = 24 x 1 + 12 x 1 + 16 x 3 +3 x ( 1 x 2 + 16 x 1)
= 138 gram
Molecular mass of H2O = 1 x 2 + 16 x 2 = 18 gram
From the balanced chemical equation
3 H2O is released from 1 MgCO3.3H2O.
∴ 3 x 18 gram of H2O is released from 138 gram of MgCO3.3H2O.
40.37 gram of H2O is released from 138 x 40.37 / ( 3 x 18) of MgCO3.3H2O
= 103.168 grams of MgCO3.3H2O