The ideal gas law describes the relationship among the pressure P, volume V, number of moles n, and absolute temperature T of an ideal gas. Here is the relationship expressed mathematically: PV = nRT, where R is a proportionality constant. The units of R are determined by the units of pressure and volume used in the equation. When atm is used for pressure and L for volume, the appropriate R value is 0.08206 L·atm/mol·K.
How many air molecules are in a 12.5×12.0×10.0 ft room (28.2 L = 1 ft^3)? Assume atmospheric pressure of 1.00 atm, a room temperature of 20.0 °C, and ideal behavior.