Thermochemical Calculations

We need to remember and apply some key calculations in our thermochemistry:

ENERGY = AMOUNT (n) × ΔH

We may need to report extra information as well, such as the mass of one of the products or reactants.

Amount, Mass and Molar Mass

There is a useful relationship between amount (n), mass (m) and molar mass (M). We use this a lot in our thermochemical calculations.

Bond Enthalpy

Every chemical bond requires a specific amount of energy to be broken. The amount of energy required to break one mole of a particular chemical bond is called its Bond Enthalpy.

We can use bond enthalpy values to calculate the enthalpy change in a reaction: