Question about Q=mcΔT when doing calorimetry

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Homework Statement



When using the equation Q=mcΔT for the substance being tested is it the mass of the substance or the mass of the substance + mass of water.

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The Attempt at a Solution



So when I solve calorimetry problems, I usually find Qwater. Then I set Qsubstance=-Qwater. But then I have to use mcΔT, I'm not sure if it's the mass of the substance or the mass of the substance + mass of the water because I've gotten a few questions wrong and the textbook briefly mentioned the sum of masses but gave no examples. Thanks for your input.
 
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Re-arrange your equation as follows:

c = [itex]\frac{Q}{mΔT}[/itex]

Since 'c' is for the substance, what would 'm' be for?
 
m is for the substance right? Not the sum of the mass of the water and substance.
 
deezer said:
m is for the substance right? Not the sum of the mass of the water and substance.
Yes, and you can relate to the definition of specific heat: energy required to raise the temperature of one unit mass of the 'substance' on unit degree.
 
edgepflow said:
Yes, and you can relate to the definition of specific heat: energy required to raise the temperature of one unit mass of the 'substance' on unit degree.

Like specific heat of brine :-p