題目如下
An ideal gas is enclosed in a cylinder with a movable piston on top.The piston has a mass of 8000g and an area of 5cm^2 and is free to slide up and down,keeping the
pressure of the gas constant.How much work is done on the gas as the temperature of 0.2
mol of the gas is raised from 20℃ to 300℃?
煩請指點!!
熱力學第一定律
2009-10-20 1:07 am
回答 (1)
2009-10-20 5:47 am
✔ 最佳答案
Universal gas constant, R = 8.31 JK^-1Work done BY the gas under constant pressure, W
= P(Vf - Vi)
as PV = nRT
P(Vf - Vi) = nR(Tf - Ti)
So, W = nR(Tf - Ti)
= (0.2)(8.31)[(300 + 273) - (20 + 273)]
= 465.36 J
So, the work done ON the gas is -W = -465.36 J
P.S. By first law of thermodynamics,
Q = U + W
Q is the heat supply to the gas
U is the increase in internal energy of the gas
W is the work done by the gas
參考: Physics king
收錄日期: 2021-04-19 15:59:53
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091019000010KK05034