Question

The temperature of 200 mL of gas

originally at STP is changed to -25 Celsius at constant volume. Calculate the final pressure of the gas in torr

Answer 1

691.6 torr

Step-by-step explanation:

Given data:

Initial temperature = 273 K

Initial pressure = 1 atm

Final temperature = -25 °C (-25 + 273 = 248 k)

Final pressure = ?

Solution:

P₁/T₁ = P₂/T₂

P₁ = Initial pressure

T₁ = Initial temperature

P₂ = Final pressure

T₂ = Final temperature

Now we will put the values in formula.

P₁/T₁ = P₂/T₂

P₂ = P₁T₂/T₁

P₂ = 1 atm × 248 K / 273 k

P₂ =248 atm. K / 273 K

P₂ = 0.91 atm

In torr:

0.91 × 760 = 691.6 torr