Physical States of Matter and Gas Laws

Flashcards covering crystalline solids, physical states of matter, properties of liquids and gases, and fundamental gas laws with their applications.

Crystalline Solids

Solids that can be homomeric (composed of one type of molecule) or heteromeric (composed of multiple types of molecules).

Heteromeric Crystals

Crystals that accommodate other types of molecules (e.g., water or counter ions) within their crystal lattice, often resulting in unique advantages like improved solubility.

Physical States of Matter

Determined by intra-particle attraction; more inter-particle attraction and less spontaneous motion lead to a denser state, while less attraction and more motion lead to a less dense state.

Liquefaction of Gas

Occurs when a gas is cooled (molecules lose kinetic energy, allowing van der Waal's forces to take over) or when pressure is applied below its critical temperature.

Critical Temperature

The temperature above which no amount of pressure can liquefy a gas, due to high kinetic energy of molecules.

Liquid Properties

Boiling point, freezing point, vapor pressure, surface tension, and viscosity.

Vapor Pressure

The pressure exerted by molecules at the surface of a liquid that have enough kinetic energy to escape attraction forces and become vapor molecules.

Volatile Drugs

Drugs (like alcohol, menthol, methyl salicylate) that have high vapor pressure at room temperature and can easily evaporate.

High Vapor Pressure Drug Handling

Requires special care (e.g., fume hood, negative pressure) due to significant exposure risks to pharmacists; excipients like polyethylene glycol (PEG) can reduce vapor pressure.

Boiling Point (BP)

The temperature at which a liquid's vapor pressure equals the surrounding atmospheric pressure.

Effect of Atmospheric Pressure on Boiling Point

Boiling point is lower in regions of low atmospheric pressure and higher in regions of high atmospheric pressure.

Surface Tension

A liquid property where molecules at the surface are pulled inwards by other molecules deeper inside, making the liquid resemble a stretched elastic membrane.

Surfactants

Agents like soap that reduce the surface tension of liquids, promoting wetting and dissolution.

Viscosity

A fluid's internal resistance to flow, commonly perceived as 'thickness,' which tends to decrease with increasing temperature.

Gaseous State

Characterized by gas molecules having little or no intermolecular attraction, with collisions against the container leading to pressure.

Pressure

Force applied over an area (Pressure = Force/Area), measured in units like Pascals, Atmospheres, mmHg, or psi.

Boyle's Law

States that the volume (V) and pressure (P) of a gas are inversely related (V "proportional to" 1/P).

Charles' Law

States that the volume (V) of a gas is directly proportional to its temperature (T) in degrees Kelvin (V "proportional to" T).

Avogadro's Law

States that the volume (V) of a gas is proportional to the number of moles (n) (V "proportional to" n).

Universal Gas Equation

PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the universal gas constant, and T is temperature in Kelvin.

Dalton's Law

States that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the component gases.

Henry's Law

States that the dissolved gas in a liquid is directly proportional to the partial pressure of the gas above the liquid.

Henry's Law Applications

Used in deepening anesthesia by increasing anesthetic gas concentration, oxygen concentrators, and understanding decompression sickness in deep-sea divers.

Aerosol Dosage Forms

Utilize propellant gases (e.g., CFC/HFA) liquefied under high pressure, which rapidly evaporate as a gas upon actuation to deliver a drug.