8.93 part c

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8.93 part c

Postby Skolli20 » Sun Jan 22, 2017 7:02 pm

8.93 says:

a) Calculate the work that must be done against the atmosphere for the expansion of the gaseous products in the combustion of 1.00 mol C6H6 (l) at 25 degrees celsius, and 1 barr. b) Using data in appendix 2A, calculate the standard enthalpy of the reaction. c) Calculate the change in internal energy of the system.

In the solutions manual, it relates delta H as being equivalent to q in the equation delta u= q+ w. My question is why can we make this assumption that the system is at constant pressure if there is expansion done in the atmosphere. Shouldn't the pressure change? Can someone please explain how to get the answer for part c? Thank you

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Re: 8.93 part c

Postby arsalzaheer2L » Sun Jan 22, 2017 11:17 pm

I was wondering about this as well!

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Re: 8.93 part c

Postby Nasir_Ahmed » Mon Jan 23, 2017 3:49 pm

I was also confused by this, but I assumed it was because it was internal energy in its standard state.

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