Estimate the speed of sound in air at standard temperature and pressure. Athe mass of 1 mole of air is 29.0 xx 10^(-3) kg.

Estimate the speed of sound in air at standard temperature and pressur

1.	Estimate the speed of sound in air at standard temperature and pressure. Athe mass of 1 mole of air is 29.0 xx 10^(-3) kg.
Answer» Solution :We know that 1 mole of any gas occupies 22.4 litres at STP. Therefore, density of air at STP is : `rho_(o) = ("mass of mole of air")// ("volume of one mole of air at STP")` `= (29.0 XX 10^(-3) kg)/(22.4 xx 10^(-3) m^(3))` `= 1.29 kg m^(-3)` According to Newton.s formula for the speed of sound in a medium, we get for the speed of sound in air at STP, `v = [(1.01 xx 10^(5) N m^(-2))/(1/29 kg m^(-3))]^(1//2) = 280 m s^(-1)` (15.23)