Question: how many molecules are in 1 atm of gas?
Answer: 1 atm = 760 torr = 760 mmHg. n = number of moles, measured in moles (recall 1 mole = 6.022x1023 molecules), abbreviated mol. T = temperature, usually measured in degrees Kelvin, abbreviated K. 273 K = 0oC, and the size of 1 degree K is the same as the size of 1 degree C.