Question

If 300 mL of a gas at 26.85°C is cooled to 6.85°C at constant pressure. What will be the final volume of gas?

Options

• 238 mL

• 210 mL

• 140 mL

• 280 mL

Answer 1

280 mL

Explanation:

V₁ = 300 mL, T₁ = 26.85°C = 26.85 + 273.15 = 300 K

V₂ = ?, T₂ = 6.85°C = 6.85 + 273.15 = 280 K

According to Charle's Law

V ∝ T

`therefore "V"_1/"T"_1 = "V"_2/"T"_2`

`(300  "mL")/(300  "K") = "V"_2/(280  "K")`

`therefore "V"_2 = (300  "mL" xx 280  "K")/(300  "K")`

= 280 mL