Chemical heat
Reaction Calorimetry Calculator
A simple coffee-cup calorimetry model estimates how much heat a solution absorbs or releases from its temperature change, then assigns the opposite sign to the reaction.
Estimate reaction heat
What the sign means
If the solution temperature rises, qsolution is positive because the solution gained thermal energy. In the simplified model, qreaction is therefore negative, which corresponds to an exothermic reaction. If the solution cools, the signs reverse and the reaction estimate is endothermic.
Why real calorimeters need calibration
A real container, probe and surrounding environment can absorb energy. More accurate calorimetry accounts for the heat capacity of the calorimeter and other losses rather than assigning every observed temperature change only to the solution.
Temperature change is not reaction enthalpy by itself
The measured temperature change depends on mass and heat capacity as well as reaction energy. Two experiments can have the same reaction heat but different temperature changes if their thermal masses differ.
Related reading
Read about exothermic and endothermic reactions, review specific heat capacity, or use the general sensible-heating calculator.