Pharmacy Thermodynamics and Physical Pharmacy

Vocabulary practice flashcards covering fundamental thermodynamic principles, processes, system types, and drug properties discussed in the pharmacy lecture.

Equilibrium Position

A state or position in which a system or object remains at the same position over time because forward and reverse rates or opposing forces are balanced.

Unstable Equilibrium

A state where a system is at equilibrium, but a slight force or perturbation causes it to leave that position and fall to a lower energy state.

Stable Equilibrium

A position where a system settles at its lowest point and returns to that position even when displaced by external forces.

Receptor

A specific surface area on cells that interacts with particular drugs or biological molecules to produce a physiological response.

Emulsion

A mixture of two immiscible liquids, such as oil and water, used in pharmacy to formulate water-insoluble substances like vitamin A or vitamin D.

Macroscopic Property

An observable thermodynamic property or outcome manifested on a large scale, such as overall solubility or change in volume, without detailing underlying mechanisms.

Microscopic Property

Atomic or molecular-level occurrences and interactions happening in the background that cause observable macroscopic outcomes.

Thermodynamic Work ($W$)

Work defined mathematically as pressure times change in volume ($W = P \times \frac{\text{V}}{1}$ or $W = P \times \text{change in volume}$); if volume change is zero ($\text{change in volume} = 0$), no thermodynamic work is performed.

System

The specific part of the universe or environment that is currently chosen as the focus of observation or discussion.

Open System

A system that allows both energy and matter to freely exchange across its boundary with the surrounding environment, such as the human body.

Closed System

A system whose boundaries are structured to prevent or minimize the exchange of matter or heat with the external environment.

Equation of State

A mathematical equation, such as $P \times V = n \times R \times T$, that defines the state and equilibrium conditions of a physical system.

Extensive Property

A thermodynamic property that depends directly on the quantity or amount of material present, such as volume, mass, or number of moles ($n$).

Intensive Property

A thermodynamic property that is independent of the amount of substance present, such as solubility, density, temperature ($T$), or pressure ($P$).

Isobaric Process

A thermodynamic process occurring at constant pressure ($P$).

Isothermal Process

A thermodynamic process occurring at a constant temperature ($T$), such as physiological metabolic reactions taking place at $37 proposal^\text{C}$ in the human body.

Adiabatic Process

A process occurring in a system without free heat exchange, where temperature changes result directly from gas expansion or compression.

Reversible Process

An ideal process occurring in infinitesimally small increments such that the system maintains equilibrium at every point throughout the process.

Irreversible Process

A real-world process that occurs rapidly and cannot spontaneously reverse itself to return to its initial state.

First Law of Thermodynamics

The law of conservation of energy, stating that energy can neither be created nor destroyed, only transformed from one form to another.

Internal Energy ($U$)

The total energy contained within a system due to molecular, electronic, vibrational, and rotational motions, macroscopically reflected as temperature.

Enthalpy ($H$)

The amount of heat absorbed or released by a system during a process occurring at constant pressure.

Heat Capacity

The amount of heat required at constant pressure to change the temperature of a given system or material by $1 touch^\text{C}$.

Molar Heat Capacity

The amount of heat required at constant pressure to raise the temperature of exactly $1\,\text{mole}$ of a substance by $1\,^\text{C}$.

Amorphous Form

A solid drug form that lacks a rigid lattice structure, resulting in faster dissolution and higher initial solubility than a crystalline form.

Crystalline Form

A solid drug form possessing a rigid three-dimensional lattice structure that must be broken down, resulting in slower dissolution and a delayed onset of action.