Which of the followin salts does not contain water of crystallisation
a) blue vitriol
b) baking soda
c) washing soda
d) gypsum
Your friends are correct,
The correct option is (b).
The baking soda does not contain water of crystallisation.
Water of crystallisation is the number of water molecules that combine chemically in definite molecular proportion, with the concerned salt in the crystalline state. This water is responsible for the geometric shape and colour of the crystals.
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