Derive the relation between density and molar mass of a gas
Answers
Explanation:
The relationships between molar mass and density for a monoatomic gas can be easy.
The Ideal Gas Law, PV = nRT can be arranged so that n moles equals the mass/molar mass of the gas to become,
PV = mRT/M
where m is the mass and M is the molar mass.
M = mRT/PV
, if you hold the temperature of the gas constant the equation reduces to the Boyle's law or
m/PV
The mass will be constant assuming the container is closed and so the gas cannot be escaped so, PV will be constant.
D = m/v
and M = mRT/PV
M = DRT/P
The higher the density of the gas the higher the molar mass and vice versa.
Answer:
Vapor density of gas = Molar mass of gas / 2
Explanation:
Vapor density of gas = Density of gas / density of standard gas
standard gas ⇒ hydrogen
Vapor density of gas = Dgas / DH₂ {D ⇒ density}
density = mass / volume
VD of gas = mass of certain volume of gas / mass of some volume of H₂
= mass of 22.4L of gas @ STP/ mass of 22.4L of H₂ @ STP
mass of 22.4L of gas @ STP = Molar mass of gas
VD of gas = Molar mass of gas / Molar mass of H₂
VD of gas = Molar mass of gas / 2