Reactivity 1.1 Enthalpy Changes in Reactions and 1.2 Energy Cycles

August 24, 2026.

1st Law of Thermodynamics

States that energy cannot be created nor destroyed, but transferred between system and surroundings.

System

Represents the reaction/chemicals or substance that is. being studied and analyzed

Surroundings

everything outside the system that can interact with the system and exchange energy with it, usually in the form of heat or work.

Heat

The transfer of thermal energy from a higher temperature object to a lower temperature object due to temperature difference

Work

energy transferred when a system moves against an opposing force, such as pressure or gravity

Internal Energy

is the total energy from all forms of kinetic and potential energy of a system

Internal energy Calculation

figure it out.

thermal equilibrium

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