The density of the gas under normal conditions (0 ° C, pressure 101 kPa) is 1.96 kg / m3. What kind of gas could it be?

Let us first recall the formula for calculating the density:

ρ = m / V,

where m is the mass (in this case, one molecule);

V is the volume of the liquid.

Formula for calculating molar mass:

M = m * Na, where

Na is Avogadro’s constant, 6 * 10 ^ 23 mol ^ -1.

Substitute in the formula for calculating the density:

ρ = M / Na * V.

We use the Mendeleev-Clapeyron law:

P * V = (m * R * T) / M.

Where P = 101,000 Pa (pressure).

T = 273 K temperature in Kelvin.

M = ρRT / P, where

R is the universal gas constant.

M = (1.96 * 8.314 * 300) / 101,000 = 0.048 grams / mol.

This gas is nitrogen (N2).