When it became too hot to stay outside during a summer birthday party, the party was moved inside to an air‑conditioned porch. If a latex balloon has a volume of 4.50 L at 39 °C, what would be the volume of this balloon at 21 °C? Assume that the pressure does not change.

PV = nRT

1)
Pressure constant:
PV = nRT
V/T = (nR/P) = constant
V₂/T₂ = V₁/T₁
V₂ = V₁T₂ / T₁
V₂ = (5.50L)(21 + 273.15) / (34 + 273.15)
V₂ = 5.27L


2)
Volume constant
PV = nRT
P/T = nR/V = constant
P₂/T₂ = P₁/T₁
P₂ = P₁T₂ / T₁
P₂ = (1.20)(545 + 273.15) / (25 + 273.15)
P₂ =3.29atm


3)
PV = nRT
PV/T = nR

P₁V₁/T₁ = P₂V₂/T₂
1.50atm(11.0L) / (23 + 273.15)K = 3.50atm V₂ / (236 + 273.15)K
V₂ = 8.10L

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