Separation

Question 1

What is Extraction?

Answer 1

The transfer of a dissolved compound from 1 solvent into another

Question 2

During extraction, most impurities remain in

Answer 2

The first solvent

Question 3

How should the two solvents be during extraction?

Answer 3

Immiscible

Question 4

Extraction separates substances based on

Answer 4

Differential solubility

Question 5

When an acid dissolves, its formed anion is

Answer 5

More soluble in the aqueous layer

Question 6

What will extract an acid in the aqueous layer?

Answer 6

Base

Question 7

Washing is a form of extraction that

Answer 7

Removes unwanted impurities instead of isolating a pure product

Question 8

Filtration is the act of

Answer 8

Isolating suspended solid from the liquid

Question 9

Gravity filtration is when the

Answer 9

Solvent is pulled out via gravity

Question 10

Gravity filtration is done with

Answer 10

Hot solvent

Question 11

Recrystallization is when

Answer 11

Impure crystals are dissolved in a minimum amount of hot solvent

Question 12

What happens to the impurities during recrystallization?

Answer 12

The impurities are left in the solution, but crystals form

Question 13

In recrystallization, the solvent should dissolve pure materials in

Answer 13

Hot temperatures

Question 14

Impurities should be dissolved in both

Answer 14

Hot and cold temperatures by the solvent

Question 15

What happens in a mixed solvent system?

Answer 15

Less soluble compound is added to a highly soluble solvent until the solid precipitates

Question 16

Sublimation is the stage in which a

Answer 16

Heated solid transforms into a gas with no liquid change

Question 17

Sublimation occurs within vacuums to allow for

Answer 17

Compounds to pass the liquid phase

Question 18

Sublimation separates solids based on their ability to

Answer 18

Sublimate

Question 19

Within sublimation, what happens to impurities?

Answer 19

They do not sublime easily

Question 20

Distillation is the act of

Answer 20

Separating a liquid from another via vaporization and condensation

Question 21

Distillation requires

Answer 21

Two or more miscible liquids

Question 22

Simple distillation separates liquids that are

Answer 22

• BP < 150

- 25º away from one another

Question 23

Vacuum distillation separates liquids that are

Answer 23

• BP > 150

- 25º away from one another

Question 24

Vacuum distillation operates under

Answer 24

Reduced pressure, which lowers the bp and prevents decomposition

Question 25

Fractional distillation separates liquids that have

Answer 25

BPs < 25º apart

Question 26

The vapor near the top in fractional distillation contains eventually

Answer 26

1 component

Question 27

Chromatography is the separation and identification of individual compounds based on

Answer 27

Differing chemical properties

Question 28

Chromatography separates components based on their ability to

Answer 28

Adhere to either the stationary or mobile phase

Question 29

In chromatography, the sample is first loaded into the

Answer 29

Adsorbent (stationary phase)

Question 30

The mobile phase of chromatography consists of

Answer 30

Fluid being run through to displace the substances

Question 31

The mobile phase causes for

Answer 31

Separation in the stationary phase

Question 32

Silica gel is

Answer 32

Polar and hydrophilic

Question 33

What kind of polarity do the original solvents have in the mobile phase?

Answer 33

Weak to moderate solvents

Question 34

Which compounds move quickly in weak to moderate polarity?

Answer 34

Nonpolar compounds

Question 35

What is the adsorbent in TLC?

Answer 35

- A piece of paper - Thin layer of silica - Alumina - Plastic - Glass Sheet

Question 36

Individual compounds with TLC can be spotted via

Answer 36

UV light

Question 37

What is the equation of Rf value?

Answer 37

Distance of compound / Distance of solvent

Question 38

What happens in Column Chromatography?

Answer 38

Compounds move up and down due to gravity

Question 39

What are the forms of adsorbents in Column Chromatography?

Answer 39

Silica gel or alumina

Question 40

In Column Chromatography, the solvent is forced through the column via

Answer 40

N2

Question 41

Ion-Exchange Column Chromatography, the beads are coated with

Answer 41

Ions

Question 42

In size-exclusion Column Chromatography, the column has

Answer 42

Beads with tiny pores, allowing large molecules to travel faster

Question 43

In a GC, what is compared?

Answer 43

Retention time

Question 44

What happens in HPLC?

Answer 44

Liquid travels though the column under pressure

Question 45

Electrophoresis separates macromolecules via

Answer 45

Charge

Question 46

What move faster in Electrophoresis?

Answer 46

Highly charged, small molecules

Question 47

Agarose is used in Electrophoresis to separate

Answer 47

Nucleic acid pieces

Question 48

Agarose is stained with

Answer 48

Ethidium Bromide

Question 49

SDS is used in Electrophoresis to separate

Answer 49

Proteins based on mass

Question 50

Isoelectric Electrophoresis has a pH at which the

Answer 50

Sum of Amino Acid charges equal to 0

Question 51

Proteins are protonoated when

Answer 51

pH < pI

Question 52

Proteins are deprotonoated when

Answer 52

pH is high

Question 53

In Isoelectric Electrophoresis, proteins move to the pt where

Answer 53

PH = pI