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1

<p>From a thermodynamics test a while back, I got this problem wrong and could never figure out how to do it. </p>

<p>"150 g of water at 20 degrees C is added to 50 g of water at 45 C. What is the temperature(in C) of the water?"</p>

<p>Once somebody posts the solution, I'll know I'm an idiot.</p>

<p>There was also another type of problem that I very,very,very,very,very,very,very,very vaguely remember that I got wrong:</p>

<p>" A bomb calorimeter is calibrated at (kj/mole or some similar units) and water raises 4 degrees C. blahblahblah...what is something?".</p>

2

<p>for the first one, I think it is 26.25 degrees C.
The heat given off by the warmer water has to be equal to the heat absorbed by the cooler water.
so use q = mass x specific heat x change in temp.
150 x 4.184 x (T - 20) = 50 x 4.184 x (45 - T)
using this you get T = 26.25 in C.</p>

<p>As per your second problem...if you could give a sample question, someone might be able to explain it.</p>

3

<p>I'm not sure if your solution is correct. I did EXACTLY what you did and got the problem worng.Maybe i did an arithmetic error.</p>