The composition of air is approximately 80% `N_(2) " and " 20% O_(2)` by mass. Calculate density of air at 298 K and 76 cm Hg pressure

The air contain 80% N_(2) and 20% O_(2) by volume. The volume occupied by 40 gm air at 27^(@)C and 760 mm Hg pressure approximately. [Given: R=0.08atm-litre- "mol"^(-1)K^(-1) ]

At sea level, the composition of dry air is approximately N_(2)=75.5% , O_(2)=23.2% , and Ar=1.3% by mass. If the total pressure at sea level is 1 "bar" , what is the partial pressure of each component?

At sea level, the composition of dry air is approximately N_(2)=75.5% , O_(2)=23.2% , and Ar=1.3% by mass. If the total pressure at sea level is 1 "bar" , what is the partial pressure of each component?

What is the density of air at STP? Assume that air contains 78% N_(2) and 22% O_(2) by masses.