Asked by Anonymous

A balloon filled with 3.5 L of helium at 20 °C and 3 atm. What will be the new pressure if its volume increases to 17.5 L at constant temperature?
Answered by Steve
PV = kT.
So, PV/T is constant. In fact, since T is constant as well, PV is constant. You want P so that

17.5P = 3*3.5