Combined gas law
A gas occupies 2.0 L at 300 K and 1.0 atm. It is heated to 450 K and compressed to 2.0 atm. What is its new volume?
Answer B: explanation for every choice
A
This inverts the temperature ratio.
B
Correct. V₂ = V₁(T₂/T₁)(P₁/P₂) = 2.0 × 1.5 × 0.5 = 1.5 L.
C
This ignores the pressure change.
D
This multiplies by the pressure ratio instead of dividing.
TakeawayP₁V₁/T₁ = P₂V₂/T₂, with T in kelvin.
Equation usedIdeal gas law
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