Molar Enthalpy of Salt: Calculation and Heat Sources

[Hannah Wallace]

So for a lab I had to test three different salt Nh4Cl,KN03 and LiCl. I found the heat of each of them and then in turn found the molar enthalpy by using N*molar enthalpy=-heat. When finding my heat and using equation mcΔt would I use the mass of the water or the mass of the water and the salt?

 

[Borek]

Note: things like "heat", "enthalpy" are properties of a process, not of a substance, so what you wrote doesn't make much sense. I guess what you mean is "heat of dissolution" and "enthalpy of dissolution" (AKA "heat/enthalpy of solution").

Mass of water and salt is a bit more correct, although technically you should also use specific heat capacity of the solution, not of the pure water. For diluted solutions using specific heat capacity of water is usually accurate enough.