A physics lecture room at 1.00 atm and 27.0o C has a volume of 216 m3. (a) Use the ideal-gas law to estimate the number of air molecules in the room. Assume that all of the air is N2. Calculate (b) the particle density—that is, the number of N2 molecules per cubic centimeter—and (c) the mass of the air in the room.

Solution 52E Step 1 of 7: Here we need to consider the N in the room as ideal gas. In case of ideal gas, the 2 interaction between the atoms or molecules inside the gas are negligible and the atom or molecule is considered to be a hard sphere, whose size is very small and negligible compared to the total volume of the gas. Such gases obeys the gas laws; Charles's law and Boyle’s law exactly at all temperatures and pressures. Such kind of gases are known as ideal gas. The state of the ideal gas can be determined by the ideal gas equation, Given by PV=NKT………………..1 Where P, V and T are the pressure , volume and temperature of the gas respectively, K is the Boltzmann constant and N is the number of molecules.