Question

A flask contains 4.4g of carbon dioxide gas. calculate how many moles CO2 gas does it contains?

Answer 1

We know,  
Molar mass of carbon dioxide = 44 grams 
That means 1 mole of carbon dioxide = 44 grams 
Here, we have given that flask contains 4.4 g of carbon dioxide 
number of moles = given mass / molar mass = 4.4 / 44 = 0.1 
Hence, 4.4 g of carbon dioxide contains 0.1 mole of CO2.