Hess's Law

Enthalpy: This is the heat content of a system at constant pressure. It's like measuring how much energy (or "heat") is in your lunchbox if it couldn't leak out anywhere.

Endothermic Reaction: This type of reaction absorbs heat from its surroundings during its process. Imagine this as an ice cream cone absorbing heat on a hot summer day and melting.

Exothermic Reaction: In contrast to endothermic reactions, exothermic reactions release heat into their surroundings. Picture this as lighting up a firework; once ignited, it releases light and heat into the air around it.