This episode explains calorimetry, the science of measuring heat transfer, based on the Law of Conservation of Energy. It demonstrates how to use the formula q=m⋅c⋅ΔT to solve for unknown variables in two common scenarios. First, the specific heat of an unknown metal is determined by measuring the heat it loses to water in a calorimeter. Second, the enthalpy change of a neutralization reaction is calculated by finding the heat absorbed by the solution and converting it to a per-mole basis. The episode highlights the importance of the negative sign in the core principle and warns against common mistakes like using the wrong mass or ignoring the negative sign.