Question

A tank of O2 used at home for a patient with pulmonary disease has a pressure of 220mmhg 2.0 moles of gas and a volume of 4.0l. What will the pressure be when the volume expands to 5.0L and 3.0 moles of O2 is added when the temperature does not change

Answer 1

Initial

pressure of oxygen(P₁)=220 mm of Hg

Pressure in atmosphere=220/760=22/76 atm

Volume of oxygen(V₁)=4.0 L

Number of mole of oxygen(n₁)=2.0

What will be the pressure(P₂) when

Volume of oxygen(V₂)=5.0 L

Number of mole(n₂)=3.0

According to ideal gas equation

PV=nRT

Temperature is constant

PV/Rn=T

P₁V₁/Rn₁=P₂V₂/Rn₂

P₂= P₁V₁Rn₂/Rn₁V₂

= 22×4×3 ÷ 76×2×5

= 0.34736842105 atm

P₂= 264 mm of Hg