A sample of argon with a volume of 6.18 L, a pressure of 761 torr, and a temperature of 20.0 degree C expended to a volume of 9.45 L and a pressure of 373 torr. What was its final temperature in degree C?

1 Answer
Mar 23, 2015

TThe final temperature will be "-53.4"^("o")"C".

You will need to use the combined gas law in order to solve this problem. The equation is:

(P_1V_1)/(T_1) = (P_2V_2)/(T_2)

Known/Given:
P_1 = 761 "torr"
V_1 = 6.18 L
T_1 = 20.0"^(o)C + 273.15 = 293.2 K (temp must be in Kelvins)
P_2 = 373 "torr"
V_2 = 9.45 L

Unknown:
T_2 in degrees Celsius

Solution: Rearrange the combined gas law equation to isolate T"2. Then solve for T_2.

T_2 = (P_2V_2T_1)/(P_1V_1) = (373 cancel ("torr")*9.45 cancel ( L)*293.2 K)/(761 cancel ("torr")*6.18 cancel (L)) = 219.8 K

Convert temperature from Kelvins to degrees Celsius.

219.8 K - 273.15 = -53.4"^(o)C