Physical Chemistry Branches

Physical Chemistry

Branches of Physical Chemistry

• Thermochemistry: study of heat and energy changes in chemical reactions
• Kinetics: study of rates of chemical reactions
• Quantum Mechanics: study of behavior of atoms and molecules at atomic and subatomic level
• Spectroscopy: study of interaction between matter and electromagnetic radiation
• Electrochemistry: study of chemical reactions involving electron transfer

Important Concepts

• State Functions: properties that depend only on the state of the system, not the path by which it was reached (e.g. internal energy, entropy)
• Extensive Properties: properties that depend on the size of the system (e.g. volume, entropy)
• Intensive Properties: properties that do not depend on the size of the system (e.g. temperature, pressure)
• Equilibrium: state in which rates of forward and reverse reactions are equal

Laws and Principles

• Zeroth Law of Thermodynamics: if two systems are in thermal equilibrium with a third system, they are also in thermal equilibrium with each other
• First Law of Thermodynamics: energy cannot be created or destroyed, only converted from one form to another
• Second Law of Thermodynamics: total entropy of an isolated system always increases over time
• Third Law of Thermodynamics: as temperature approaches absolute zero, entropy of a perfect crystal approaches a minimum value

Important Equations

• Ideal Gas Law: PV = nRT
• Gibbs Free Energy: ΔG = ΔH - TΔS
• Arrhenius Equation: k = Ae^(-Ea/RT)

Branches of Physical Chemistry

• Thermochemistry is the study of heat and energy changes in chemical reactions.
• Kinetics is the study of rates of chemical reactions.
• Quantum Mechanics is the study of behavior of atoms and molecules at atomic and subatomic level.
• Spectroscopy is the study of interaction between matter and electromagnetic radiation.
• Electrochemistry is the study of chemical reactions involving electron transfer.

Important Concepts

• State Functions are properties that depend only on the state of the system, not the path by which it was reached (e.g. internal energy, entropy).
• Extensive Properties are properties that depend on the size of the system (e.g. volume, entropy).
• Intensive Properties are properties that do not depend on the size of the system (e.g. temperature, pressure).
• Equilibrium is a state in which rates of forward and reverse reactions are equal.

Laws and Principles

• The Zeroth Law of Thermodynamics states that if two systems are in thermal equilibrium with a third system, they are also in thermal equilibrium with each other.
• The First Law of Thermodynamics states that energy cannot be created or destroyed, only converted from one form to another.
• The Second Law of Thermodynamics states that the total entropy of an isolated system always increases over time.
• The Third Law of Thermodynamics states that as temperature approaches absolute zero, the entropy of a perfect crystal approaches a minimum value.

Important Equations

• The Ideal Gas Law is expressed as PV = nRT.
• The Gibbs Free Energy is expressed as ΔG = ΔH - TΔS.
• The Arrhenius Equation is expressed as k = Ae^(-Ea/RT).