A helium-filled balloon has a volume of 2.75 L at 20∘C. The volume of the balloon decreases to 2.46 L after it is placed outside on a cold day. What is the outside temperature in ∘ C?
10.9∘C
According to Charles' Law,
V1T1=V2T2
where V1=2.75 L :T1=20∘C=(273+20)K=293 K : V2=2.46 L
⇒T2=V2T1V1
⇒T2=2.46×2932.75=262.1
Hence, the final temperature =262.1K=(262.1−273)∘C=10.9∘C