A sample of helium gas has a volume of 1.34 L at 129 K and 4.00 atm. When the gas is compressed to 0.449 L at 40.0 atm the temp increases markedly. What's the final temperature?

Answer 1

When you see a problem dealing with gases in chemistry that involves volume, temperature, and pressure change, you can utilize the Combined Gas Law Equation to solve the problem:

Combined Gas Law:

[ (Pressure @ t1 ) x (Volume @ t1 )] / (Temp @t1 ) = [ (Pressure @ t2 )x (Volume @ t2 ) ] / (Temp @ t2 )

t1 and t2 stand for two different times, usually an initial and a final time

Since all of the values given are in the same units, I can just plug into the above equation to solve for temperature:

[ (4.00 atm) (1.34L) ] / (129K) = [ (40.0 atm) (0.449L) ] / (Temp @ t2)

Temp @ t2 = [(40.0atm)(0.449L)(129K)] / [(4.00atm)(1.34L)]

Temp @ t2 = 432K (3 sig figs)