Question

2. Calculate the mass density of air at the surface of the Earth using the ideal gas law and assuming global average values of surface pressure (984 hPa) and temperature (288 K).

Answer 1

PV =nRT

$\therefore \rho=\frac{PM_w}{RT}$

Where $\rho=$ Density

$P=$ Pressure

$M_w=$ Molar weight of air$=28.97g/mol$

$R$ $=$ Gas constant$=8.314$

$T=$ Temperature

$\rho=\frac{984×100×28.97×10^{-3}}{8.314×288}$

$=1.191kg/m^3$