## HW 8.13 & Heat Absorption

Michelle_Nguyen_3F
Posts: 40
Joined: Wed Sep 21, 2016 2:59 pm

### HW 8.13 & Heat Absorption

"In a combustion cylinder, the total internal energy changes produced from the burning of a fuel is -2573 kJ. The cooling system that surrounds the cylinder absorb 947 kJ as heat. How much work can be done by the fuel in the cylinder?"

I know to use $\Delta U$ = q + w. So $\Delta U$ = -2573 kJ and q = -947 kJ. However, why is it that the 947 kJ that is absorbed negative? Thank you!

Chem_Mod
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### Re: HW 8.13 & Heat Absorption

The cooling system is absorbing 947 kJ of heat from the combustion cylinder, so the system is losing heat.

Jata_Kavya_3A
Posts: 22
Joined: Wed Sep 21, 2016 2:57 pm

### Re: HW 8.13 & Heat Absorption

if the system is losing heat, then the internal energy of the system decreases because q is negative. Vice versa, if the system absorbs or gains heat.

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