(adsbygoogle = window.adsbygoogle || []).push({}); 1. A gas bottle with a volume of 0.1 m3 contains 0.4 kg of a gas at a pressure of 7

MN/m2 and a temperature of 150 ºC. For this gas Cp = 10.54 kJ/kg K. Calculate

the changes in internal energy when temperature is raised to 500K

Given answer: 362 kJ

2. pV=mRT pv=RT

mCpdT=dH

mCvdT=dU

dq-dw=du

3. so i've been struggling with this for a while. i know that du=dq as there is no net work when volume is constant.

initially i used p1V1/mT1=R and then i used Cp=R+Cv to find Cv. From there i used the equation mCvdT=dU. however this doesnt give the correct answer.

ive been trying a few other ways as well but they havent worked. is there some assumption i can make etc...?

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Thermodynamics change in internal energy

**Physics Forums | Science Articles, Homework Help, Discussion**