text: can anyone help? an ideal gas occupies a volume of 2.2 cm3 at 20°c and atmospheric pressure. determine the number of molecules of gas in the container. = 5.65e19  if the pressure is reduced to 2.6  10-11 pa (an extremely good vacuum) while the temperature remains constant, how many moles of gas remain in the container? use pv=nrt, the ideal gas law, and some algebra  n= number of moles present.  each mole contains 6.02 * 10^23  atoms  n=pv/rt and remember to convert everything to their proper units before doing the calculation ie change celcius to kelvin etc