Ideal Gas Equation Help!

Question

A house has a volume of 1.45 x 10^4 cubic meters. At 20.0°C and 740 mm Hg, the air fills the house. If the temperature and pressure increases to 35.0°C and 780 mm Hg, how much air must be drawn into the house to accommodate the change in volume of the air?

Answer 1

Start with P V = n R T

(pressure) (volume) = (moles) (gas constant) (temperature)

n is the initial number of moles of gas in volume V at P and T

n = V P / R T

n' is the final number of moles of gas in volume V at P' and T'

n' = V P' / R T'

You will have the number of additional moles, n", from

n" = n' -n

and you can get the "how much air" (?) answer from that number of moles

or from the volume, V", that many moles will occupy at that new P', T' combination.