A sample of argon has a volume of 205 cm^3cm3 when it's temperatures is -44 degrees C. and its pressure is 712 mm of Hg. What would be the volume of the argon at STP?

1 Answer
Jul 3, 2017

We use the combined gas law, which states for a GIVEN quantity of gas..........(P_1V_1)/T_1=(P_2V_2)/T_2P1V1T1=P2V2T2; and we eventually get V_2~=230*cm^3V2230cm3

Explanation:

TT is always expressed as "temperatura assoluta"temperatura assoluta, which sets absolute zero at 0*K-=-273.150K273.15 ""^@CC. And depending on your syllabus, STPSTP specifies a temperature of 273.15*K273.15K, and a pressure of 1*atm1atm. And we know that 1*atm1atm will support a column of mercury that is 760*mm760mm high.........

We want V_2=(P_1xxV_1xxT_2)/(P_2xxT_1)V2=P1×V1×T2P2×T1.....

And already we see from the quotient we ARE going to get an answer with "VOLUME units........"VOLUME units........ as required.

V_2=(712*mm*Hgxx205*cm^3xx273.15*K)/(760*mm*Hgxx229.15*K)V2=712mmHg×205cm3×273.15K760mmHg×229.15K

~=230*cm^3230cm3...........