Question

4 g CH4, 4g N, and 4 g 0, are enclosed in a chamber of 1 litre at 27°C. What is the total
pressure ? (R=0.082 atm L K-1 mol-1)​

Answer 1

Given info : 4 g CH4, 4g N2, and 4 g 02 are enclosed in a chamber of 1 litre at 27°C.

To find : the total pressure in the chamber would be ...

solution : no of moles of CH₄ , n₁ = mass of CH₄/molecular mass of CH₄

                                                 = 4g/16g/mol = 0.25 mol

no of moles of N₂ , n₂ = mass of N₂/molecular mass of N₂

                              = 4g/28g/mol = 0.143 mol

no of moles of O₂ , n₃ = mass of O₂/molecular mass of O₂

                             = 4g/32g/mol = 0.125 mol

so the total no of moles of gases , n = n₁ + n₂ + n₃

                                                      = 0.25 + 0.143 + 0.125 = 0.518 mol

now using gas equation, PV = nRT

⇒ P × 1 Litre = 0.518 mol × 0.082 atm. Litre K⁻¹ mol⁻¹

⇒ P = 0.42476 atm

therefore the total pressure in the chamber is 0.42476 atm.