Gen Physics HW Help: Ideal Gas Law and Temperature Change

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To determine the fraction of air molecules that must be pushed outside as the furnace raises the temperature from 16°C to 20°C, the ideal gas law (PV = NkT) is applied. The key is to convert temperatures to Kelvin for accurate calculations, as absolute temperature is essential in gas law equations. The ratio of the number of molecules before and after heating can be expressed as N2/N1 = T2/T1. The calculation shows that N2 equals approximately 0.80N1, indicating that about 20% of the air must be expelled. The provided answer of 0.0136 seems inconsistent with the calculations based on the temperature change.
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HW Help: Absolute temp and ideal gas law

Homework Statement


What fraction of the air molecules in a house must be pushed outside while the furnace raises the inside temperature from 16C to 20C? The pressure does not change since the house is not 100% airtight.


Homework Equations


PV=NkT
PV/T=PV/T
?


The Attempt at a Solution


NkT=NkT? N2/N1 = T2/T1. N2 = .80N1. Answer provided is .0136. I can't figure how that answer comes about. Help would be grateful. Thanks.
 
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You need to take the temperature ratio in degrees Kelvin i.e. T=0 should be absolute zero.
 
Assuming the pressure inside the house does not change, your formula is correct. It's OK to solve in degrees C, the answer is relational.
 

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