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Grade 12th passPhysical Chemistry

Air contains 23% oxygen and 77% nitrogen. Them % of Oxygen in volume

Profile image of Ankita das
8 Years agoGrade 12th pass
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1 Answer

Profile image of Arun
8 Years ago
Consider we have 100 g of air. 
Mass of oxygen in 100 g of air = 23 g
Mss of nitrogen in 100 g of air = 77 g
Molar mass of Oxygen = 32 g
1 mole of oxygen or 32 g of Oxygen occupy 22.4 L volume so 23 g of oxygen will occupy 22.432×23
= 16.1 L
Similarly, 28 g of Nitrogen occupy 22.4 L, so 77 g of Nitrogen will occupy 22.428×77
= 61.6 L
Total volume of air = 16.1 + 61.6
= 77.7 L
% by volume of Oxygen = 16.177.7×100
= 20.7 %