Question

A litre of an ideal gas at 27°C is heated at constant pressure to 297°C. The approximate final volume of the gas is?

Options

• 1.2 litres

• 1.9 litres

• 19 litres

• 0.9 litres

Answer 1

1.9 litres

Explanation - 

Given,

Initial volume of an ideal gas, V₁ = I litre

lnital temerature of an ideal gas, T₁ = 27° C 

= =27 +273 =300k

Final temerature ofan ideal gas,T₂ = 297° C

= 297 +273 =570 k

Using ideal gas equation= 570 k

PV = nRT

At constant pressure, V ∝ T ( ∵ n and R are constant)

∴ ${\displaystyle \frac{{\text{V}}_1}{{\text{V}}_2}=\frac{{\text{T}}_1}{{\text{T}}_2}\Rightarrow {\text{V}}_2=\frac{{\text{V}}_1{\text{T}}_2}{\text{T}}}$

${\displaystyle \Rightarrow {\text{V}}_2=\frac{1\times 570}{300}=1.9}$ litres