Chemical analysis Flashcards
what is everyday purity?
-nothing added to it e.g beeswax
what is chemical purity?
-only contains one element or compound
how to test purity of sample?
- have specific m/bpts
- compare with m/bpts in data book
closer measured value to actual, purer the sample
what do impurities do to samples?
-lower mpt and increase range
increase bpt and increase range
what are formulations?
- useful mixture with precise purpose made by formula
- measured quantities of components contributes to properties so it meets function
paints are formulations composed of:
- pigment: colour e.g titanium oxide in white paints
- solvent: dissolve components and alter viscosity
- binder: forms film holds pigment in place after painted on
- additives: further change physical and chemical properties
how are formulation important in pharmaceutical industry
- alter formulation of pill so delivers to right body part
- right conc
- consumbale
- long shelf life
info on composition is found on labels
- ratio or percentage of each component
- choose formulation with right composistion of particular use
what is a mobile phase?
-molecules can move in liquid or gas
what is a stationary phase?
molecules can’t move in solid or real thick liquid
what effects how quick chemical moves or how spots are formed?
- distribution: more time in m than s moves further up paper
- spots form if chemicals spend diff time in m
- no. of spots depend on solvent
- pure substance forms one spot in any solvent
amount of time molecules spend in each phase depends on?
- solubility of solvent
- how attracted to paper
- higher solubility and less attraction means longer in m
what is the Rf value and its calculation?
- ratio between distance travelled by solute and solvent
- distance by solute/distance by solvent
how to test for chlorine?
- bleaches damp litmus paper white
- red for a sec cuz acidic
how to test for oxygen?
glowing splint inside test tube and will relight
how to test for CO2
bubble it thru aquaeous solution of limewater, turns cloudy