## positive or negative values

$\Delta U=q+w$

Crystal Escobar 1F
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

### positive or negative values

How do we determine whether a the values of w, q, or U are negative or positive?

Spencer Johnson 1C
Posts: 9
Joined: Fri Sep 25, 2015 3:00 am

### Re: positive or negative values

It usually depends on the wording of the question. For example, if heat is absorbed by the system q is positive and the reaction is endothermic but if heat is released then q is negative and the reaction is exothermic.