Q3 of 10 Page 46

Calculate the percentage composition of carbon and Oxygen in CO2. (given atomic masses : Carbon =12 and oxygen =16)

The percentage composition of an element in a compound is the mass of an element present in 100g of that compound.


The mass percentage of an element


Now, Total mass of CO2 = 12 + 2×16 = 44


Percentage composition of carbon in CO2 =


= 27.27%


Percentage composition of oxygen in CO2 =


= 72.73%


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