If 17 L of a gas at a temperature of 67°C and a pressure of 88.89 atm has its temperature increased to 94°C and its volume decreased to 12 L, what is the new pressure?

1 Answer
Feb 12, 2017

Answer:

The new pressure will be #"140 atm"#.

Explanation:

This is an example of the combined gas law. The equation to use is:

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

where #P# is the pressure, #V# is the volume, and #T# is the temperature in Kelvins. For this question, the temperature in degrees Celsius will be converted to Kelvins by adding #273.15#.

Write what you know.

#P_1="88.89 atm"#
#V_1="17 L"#
#T_1="67"^@"C" + 273.15="340 K"#
#V_2="12 L"#
#T_2="94"^@"C" + 273.15="367 K"#

Write what you don't know: #P_2#

Solution
Rearrange the equation to isolate #P_2#, substitute the known values into the equation, and solve.

#"P_2=(P_1V_1T_2)/(V_2T_1)#

#P_2=(88.89"atm"xx17"L"xx367"K")/(12"L"xx340"K")="140 atm"# rounded to two significant figures