Answer:
The identity of the gas is Cl₂ (chlorine)
Explanation:
STP conditions are:
1 atm → Pressure
273.15 K → T°
So, we must use the Ideal Gas Law to get the moles.
Before that, we will think density as data where 3.164 g of diatomic gas are contained in 1 L of volume.
P.V = n . R . T
1 atm . 1 L = n. 0.082 L.atm/mol.K . 273.15K
1 L.atm / (0.082 L.atm/mol.K . 273.15K) = n
0.0446 mol = n
This quantity of diatomic gas, are 3.164 g so the molar mass will be:
Mass / mol = molar mass
3.164 g / 0.0446 mol = 70.9 g/m
The element (a diatomic molecule), which has that molar mass in the periodic table is the Cl₂.
1 Cl = 35.45 g/m
Cl₂. = 70.9 g/m