Two Phase Systems Flashcards
what can physical properties include?
- particle size + surface area
- solubility
- dissolution
- crystal properties
- stability
- organoleptic (taste, odour, colour)
what does physical stability mostly refer to?
- visual + organoleptic appearances
- 2 phase systems (solid-lie phases)
define crystal?
chemically well defined
have high degree of order for atoms/mol
what are the ideal crystals?
perfect arrays in which building blocks arranged according to well defined symmetries into unit cells that are repeated in 3 dimensions
ideal body = crystalline
what is amorphous material?
atoms + mol that are arranged in random manner, disordered state
e.g glass
define crystallisation?
transition of chemical from liquid solution state into solid crystalline state
what is a solute?
chemical that is in liquid solution state
what is a solvent?
liquid in which solute dissolved
what is an anti-solvent?
liquid in which solute = insoluble
what is nucleation?
formation of small mass (crystal nuclei)
what is homogeneous nucleation?
pure mol of solute crystallise
what is heterogenous nucleation?
catalytic formation of crystal around impurity
define crystal growth?
addition of more solute mol to formed nuclei
what are supercritical fluids?
substances above critical temperature + pressure
supercritical fluids combine properties between gas + liquid, what are they?
- viscosity + dispersion
- density
