Chemistry exam 15.06-16 Flashcards
Define azeotropes
Anazeotropeor aconstant boiling mixtureis amixtureof two or more liquids whose proportions cannot be altered by simpledistillation.
2 examples of azeotropes
- Positive: Ethanol
- Negative: Hydrochloric acid
Define colligative properties
Properties ofsolutionsthat depend on the ratio of the number of solute particles to the number ofsolventmolecules in a solution, and not on the type of chemical species present.
2 examples of colligative properties
- Elevation of boiling point
- Depression of freezing point
Define the third law of thermodynamics
Regarding the properties of systems in equilibrium at absolute zero temperature:
Define Avogadro’s law
Equal volumes of all gases, at the same temperature and pressure, have the same number of molecules
Wright Van der Waals equation
(P+(an^2/v^2) (V-nb)=nRT
Nernst equation for Zn
lnQ= ln (conc of reduced component/conc of oxidized component)
lnQ= ln(Zn2+/Zn)
Define internal energy (equation)
Inthermodynamics, theinternal energyof asystemis theenergycontained within the system*
∆U ≝ Q + W
Stabilizers of colloids
- electrical charge
- hydration (solvation)
- protective colloids
Name a non-ionic surfactant and a cationic surfactant
Non-ionic surfactan:
- fatty alcohols,
- Cetyl alcohol,
- Stearyl alcohol,
- Cetostearyl alcohol
- Oleyl alcohol.
Cationic surfactant:
- Bronidox
- Thonzonium bromide
- Pahutoxin
- Olaflur
Define reverse osmosis
Reverse osmosis(RO) is a water purification technology that uses asemipermeable membraneto removeions, molecules and larger particles from drinking water.
Define retention factor is TLC
Rf= distance traveled by the compound/ distance traveled by the solvent front
0 < Rf < 1
Which is an example of a thickener?
Xanthan gum, Gum Arabic, Gum Tragacanth, Guar gum, Locus bean gum, Gellan gum, Sodium Alginate, Carrageenans, Kappa
Which of the following contains phosphorous: DNA, DDT …
DNA
