Answer : The approximate mass of 
 is 65 grams.
Explanation :
First we have to calculate the moles of 
.
As, 
 molecules of 
 present in 1 mole of 

So, 
 molecules of 
 present in 
 mole of 

Now we have to calculate the mass of 
.

Molar mass of 
 = 98 g/mole

Therefore, the approximate mass of 
 is 65 grams.