Separation Tech And Qualitative Analysis Flashcards
Define Pure Substance
A pure substance is made up of 1 single element or compound. It is not mixed with any other substances.
What is filtration used for?
To separate a insoluble solid from a soluble solid.
What is Rf value?
Distance travelled by substance÷distance travelled by solvent
Recall the properties of pure solids
A solid is pure if it has an exact or fixed melting point
What is one reason for the importance of purity?
Impurities in drugs and medicine may cause undesirable side effects.
What decides the distance the chromatogram travels?
The solubility of the sample in the solvent.
What are the directions of water in/out of the condensers?
Enter from bottom
Leave from top
What metals give white precipitates?
And which of these metals are soluble in NaOH?
Ca/Al/Pb/Zn
Al/Pb/Zn (Zn soluble in NH³[aq] as well)
Fe² and Fe³ precipitate colour in NaOH and NH³?
Fe²: Green
Fe³: Red Brown
Cu² rxn with NaOH:
Cu² rxn with NH³
NaOH: Blue precipitate
NH³: Blue precipitate soluble in excess to form dark blue solution.
What substance do we add for all Anion tests?
Barring NO³
HNO³.
What do we add to test for Cl and SO⁴?
Cl: AgNO³
SO⁴: BaSO⁴
