Question

what will be the pressure exerted by a mixture of 3. 2 grams of CH4 and 4. 4 grams of CO2contained in a flask of volume of (9*10^-3 m^3)at 27°C ?

My solution :
PV= nRT
Moles in CH4 = 3.2/16=0.2 moles
Moles in CO2 = 4.4/44=0.1moles
Total moles = 0.3moles
P*(9*10^-3 m^3) = (0.3 mol)(8.314 pa m^3 K ^-1 mol^-1)(300K)




Is it correct ???????

Answer 1

Let's apply Ideal gas law: P V = n R T

T = 300°K.
V = 9 dm^3 = 9 * 10⁻³ m³ or 9 L

Molecular mass of Methane: CH4 =16.
of Carbon Dioxide CO2 = 44.

Total Number of moles of the gases in the mixture:
n = n1 + n2
= 3.2/16 + 4.4/44
= 0.3 mol

R = 8.318 J/°K
P = n R T / V
= 0.3 mol × 8.314 J/°K/mol × 300°K / 0.009m³

P = 0.8314 bar or 8.314 * 10⁴ Pa or 0.83 atm

Hope this helps :)