# How much heat is gained/released based off of equation?

Using this equation, $\ce{CaCl2(s) -> Ca^{2+}(aq) + 2Cl^{-}(aq)}$

and $\Delta H = - 325.0 \; kJ$

If you have 15.0 grams of the solid, how much heat is released or gained in kilojoules?

• Are you sure you have the right units for $\Delta H$?
– LDC3
Commented Apr 20, 2014 at 20:54
• @ldc3 Ya, it was a given value for the problem. Commented Apr 20, 2014 at 20:58
• Suppose you dissolve a gram of calcium chloride and then a kilogram, both in excess water. They cannot each and both be the value you posted. If you have the correct units, the path to a correct answer is obvious. Open your textbook. The first time you do it there is a crackling sound. Google it, "enthalpy of solution". BTW, the value is for infinite dilution. Commented Apr 20, 2014 at 21:03
• $\Delta H$ is usually in $kJ/mol$. That is why I am asking. Either the question has a mistake or maybe it is $\Delta H^°$
– LDC3
Commented Apr 20, 2014 at 21:03
• @LDC3 I updated the post with a picture of the question. It very may well be kJ/mol but it isn't stated. Commented Apr 20, 2014 at 23:06