Based on the question, it is evident that the question is based on Boyle's Law which we will use to find the answer necessary.
Now, Boyle's Equation: P₁V₁ = P₂V₂
P₂ = P₁V₁ ÷ V₂
∴ P₂ = (0.450 L × 1 atm) ÷ 2 L [plz note that 450 ml = 0.450 L]
⇒ P₂ = 0.225 atm Thus, the pressure when the volume has increased to 2 L is 0.225 atm [OPTION A].
