Ideal Gas Question Homework: Mass of Air in House @ 20C & -10C

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The discussion revolves around calculating the mass of air in a house with a volume of 770 m^3 at two different temperatures: 20°C and -10°C. The mass of air at 20°C is determined to be 924 kg using the density of air at that temperature. To find the mass of air that enters or leaves the house when the temperature drops to -10°C, the ideal gas law is applied. The formula V1T1 = V2T2 is suggested to find the new volume at -10°C, which can then be used to calculate the change in mass based on the density of air at that temperature. This approach provides a systematic method to solve the problem.
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Homework Statement


A house has a volume of 770 m^3. (a) what is the total mas of air inside the house at 20 Celsius? (b) If the temperature drops to -10 Celsius, what mass of air enters or leaves te house?


Homework Equations



PV = nRT

The Attempt at a Solution


I found the solution for part a which I think 924 kg. I found this answer by multiplying 770 m^3 by 1.2 kg (density of air at 20 Celsius: 1.2kg/m^3).
But I do not know how to find the answer to part b. I read the whole chapter but still did not know how. Please help me.
 
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tiffanysnow said:

Homework Statement


A house has a volume of 770 m^3. (a) what is the total mas of air inside the house at 20 Celsius? (b) If the temperature drops to -10 Celsius, what mass of air enters or leaves te house?
Using the formula
V1T1 = V2/T2
find V2.
Then find the change in volume. Multiply it with density to get the mass air entering the room.
 

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