How much thermal energy is in the air in a room with volume 29 m3 at 0.2 ◦C?

May 2021 2 132 Report

How much thermal energy is in the air in a room with volume 29 m3 at 0.2 ◦C?

How much thermal energy is in the air in a

room with volume 29 m3 at 0.2 ◦C? Assume

that the pressure remains at 1.013 × 105 Pa.

Answer in units of J.

I cannot figure out which equation to use. Any help would be greatly appreciated.

Hello Agent : Calculate amount of air in the room. Then calculate Delta U from chosen datum for zero thermal energy :

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m = ( P ) (V ) ( M ) / ( R ) ( T )

m = ( 1 atm ) ( 29,000 L ) ( 28.97 g / gmol )/ ( 0.08205 ) ( 273.4 )

m = 37450 g

R = 0.08205 atm - L / gmol - K

Set u = 0.0 J / g at 0.0 K:

Delta U = ( m ) ( CV ) ( T - Tbase )

Delta U = (37450 ) ( 0.718 J / g - K ) ( 273.4 - 0.0 )

Delta U = 7.352 x 10^6 J

U = 7.352 x 10^6 J relative to 0.0 K <---------------------------------------