Study Set Content:
The more viscous a liquid is, the greater is the (blank)
required to make it flow at a particular rate.
applied force
depend upon the number of moles of
solute present in given mass of solvent.
Colligative properties
It does not depend on (blank) of solute particles.
nature
are not simple molecules, they are aggregations of
molecules.
Colloidal
particles
Hence, all colloidal dispersion give low value of
osmotic
pressure, depression in freezing point and elevation in boiling
point.
Is defined as a heterogeneous, two phase system in which
the internal (dispersed, discontinuous) phase is distributed
or dispersed within the continuous (external) phase or
vehicle.
Disperse system
Are heterogeneous dispersed systems, in which the dispersed
phase particles are larger than 1000 nm.
COARSE DISPERSIONS
Characterized by relatively fast sedimentation of the dispersed
phase caused by gravity or other forces.
COARSE DISPERSIONS
Dispersed phase of coarse dispersions may be easily separated
from the continuous phase by
filtration
COARSE DISPERSIONS
includes
a. Suspensions
b. Emulsions
Classification of Suspensions base on electrokinetic nature of solid particles
Flocculated suspension
Defllocculated suspension
Sediments faster and is easy to redisperse
Flocculated suspension
Sediments slowly and is difficult to redisperse
Deflocculated suspension
Typically, the suspensions with particle size greater than ~1 μm
are classified as coarse suspension, while those below 1 μm are
classified as
colloidal suspension
When the particles constituting the internal phase of the
suspension are therapeutically active, the suspension is known
as
pharmaceutical suspension.
Suspended material should not
settle rapidly
The particle that do settle to the bottom of the container must
not form a hard cake but should be readily re-dispersed into a
uniform mixture when the container is
shaken
The suspension must not be too viscous to pour freely from
the orifice of the bottle or to flow through a
syringe needle
should be sterilizable
Parenteral/Ophthalmic suspension
It should have
pleasing odor, color and palatability
