There is gas in a gas container. A valve on the container will be opened and a quarter of the gas quantity will be released to the outer range. Due to this process the temperature of the gas will be decreased by 20%. What is the decrease of the gas pressure?

Answer 1

p1v1=nRT
P2V2=.75nRt2
V1=V2

P2=.75nRT2P1/nRT1

but T2=.8T1
P2/P1=.75*.8=.6
soPressure 2 is sixty percent of the original pressure.
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