Question

your teacher gave you two substances X And Y. she said that X had no water of crystallization, and that Z was obtained by heating Y in vaccum. What could X, Y and Z possibly be?

Answer 1

Answer:

x=water

y=compound used to make chalk

z=drying agent

Explanation:

A compound 'x' on losing partial crystallization of water gives compound 'y' which is used for making chalk and other pottery articles. But when 'x' is strongly heated, it gives 'z' which is used as drying agent. 

Answer 2

X is Copper sulphate pentahydrate.

• In general blue vitriol is nothing but copper sulphate and it is hydrated with 5 moles of water to form copper sulphate pentahydrate. Blue vitriol:- CuSO4. 5H2O.
• It had been heated to evaporate the water content in it this it had no water of crystallization.
• Graphite is the most stable allotrope of carbon and hence all other allotropes turn into graphite at higher temperatures. Diamond turns into graphite at a temperature between 1800K and 2000K in a vacuum. Thus Z is graphite which is obtained and Y is diamond.