Question

what is the percentage of water in the hydrate CoCl2*6H20?

Answer 1

You are given the hydrate CoCl2.6H20. You are required to get the percentage of water in this chemical substance. The first thing to do is to get the molar mass of CoCl2.6H20 and CoCl2. The molar masses are 237.8 grams per mole and 129.8 grams per mole respectively. The formula in getting the percentage of water is  

%=[1-(grams of CoCl2/grams of CoCl2.6H20)]*100.  

Substitute the molar masses of CoCl2.6H20 and CoCl2.  

%=[1-(129.8 grams of CoCl2/237.8 grams of CoCl2.6H20)]*100.
% of water = 45.42%

Answer 2

Answer : The percentage of water in the hydrate $CoCl_2.6H_2O$ is, 45.39 %

Explanation :

As we know that,

The molar mass of $CoCl_2.6H_2O$ = 237.93 g/mole

The molar mass of water $(H_2O)$ = 18 g/mole

The molar mass of $6\times (H_2O)$ = 6 × 18 g/mole = 108 g/mole

Now we have to calculate the percentage of water in the hydrate $CoCl_2.6H_2O$

$\%\text{ of water}=\frac{\text{Molar mass of }CoCl_2.6H_2O}{\text{Molar mass of }H_2O}\times 100$

Now put all the given values in this formula, we get the percentage of water in the hydrate $CoCl_2.6H_2O$

$\%\text{ of water}=\frac{108g/mole}{237.93g/mole}\times 100=45.39\%$

Therefore, the percentage of water in the hydrate $CoCl_2.6H_2O$ is, 45.39 %