Lab Defenitions Flashcards
Density
The density of a liquid is defined as mass per unit volume
Relative density
The relative density of any liquid at a given temperature means the relative density of the liquid at that temperature with respect to the density of water
Viscosity
Fluids resistance to flow
Relative viscosity
Measure of resistance of a fluid compared to that of water
What is the viscometer used?
Ostwalds viscometer
Define partition coefficient
A measure of the lipophilicity and hydrophilicity of a substance
Define buffer
Compounds that resist changes in pH upon the addition of small quantities of strong acid or strong base
Define buffer capacity
The ability of a buffer to resist pH changes when acid or base is added
Smaller the pH changes the greater the buffer capacity
Define liquid dosage form
Pharmaceutical dosage form that is in a liquid state containing active ingredient
Define Solution
An evenly distributed mixture of one or more dissolved medications in a liquid vehicle
Define solvent
Could be aqueous or oleaginous, used in the preparation of a solution to dissolve another substance
Define syrup
A sweet concentrated aqueous solution of sugar in water
Aqueous solution
Solution that is prepared with water being the solvent
Non-aqueous solution
A solution prepared with solvent other than water such as ethanol, glycerin, propylene glycol and certain oils
Aromatic water
A clear aqueous solution of volatile oils or other volatile substances
Elixir
A clear sweet solution that contains dissolved medication in a base of water and ethanol
Spirit
An alcoholic or hydro-alcoholic solution that contains volatile, aromatic ingredients
Surface tension
Tension which exists on the molecules at the surface of the liquid
Interfacial tension
The tension that exists on the liquid at the surface of another liquid
What are the methods to measure surface tension
Capillary rise method
Drop weight method
Drop number method
Emulsion
A blend of two immiscible liquids
Dispersion
When the medication is not dissolved, but distributed throughout the vehicle
Suspension
A biphasic system of coarse dispersion where insoluble particles which are greater than1um in diameter are dispersed in a liquid or aqueous vehicle
LVP
Solutions that are typically bags or bottles containing more than 100ml for intravenous solution
