Dumbledore decides to gives a surprise demonstration. He starts with a hydrate of Na2CO3 which has a mass of 4.31 g before heating. After he heats it he finds the mass of the anhydrous compound is found to be 3.22 g. He asks everyone in class to determine the integer x in the hydrate: Na2CO3·xH2O; you should do this also. Round your answer to the nearest integer.

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

1. they vary with a higher number because boiling is way hotter than melting