Answer : The integer 'x' in the hydrate is, 2
Explanation : Given,
Mass of hydrate
= 4.31 g
Mass of anhydrous
= 3.22 g
First we have to calculate the mass of water.
Mass of water = Mass of hydrate
- Mass of anhydrous 
Mass of water = 4.31 g - 3.22 g
Mass of water = 1.09 g
Now we have to calculate the moles of
and 

Molar mass of
= 18 g/mol

and,

Molar mass of
= 106 g/mol

Now we have to calculate the ratio of
and 

The formula of compound is, 
The value of 'x' is, 2
So, the formula of compound is, 
Thus, the integer 'x' in the hydrate is, 2