### Calculating final temperature of a substance

Posted: **Thu Jan 21, 2016 10:49 pm**

by **Joann Hernandez 2F**

When you are given the mass at a certain temperature for substance A, then mass at a different temperature for substance B, are those temperatures correlated to each other and work for both substances (as T initial and T final for both?) If not, how do I find the final temperature of substance B??

### Re: Calculating final temperature of a substance

Posted: **Fri Jan 22, 2016 12:43 am**

by **Jacqueline Lee**

I'm assuming you're adding the two substances together that then reaches a final temperature.

Because the two substances will then share a final temperature, I use the equation q_{1}=q_{2} therefore mCpT=mCpT

Our unknown would then be x, which is the final temperature, not the change in temperature.

So the you can set up the equation as normal, be remember that the hotter given temperature will go down to x (temp_{hotter}-x) and the cooler temperature will rise to x (x-temp_{cooler}).

mCp(temp_{hotter}-x)=mCp(x-temp_{cooler})

Then you can solve for x, the final temperature of both substances.