Organic synthesis and analytical techniques

Question 1

name greenhouse gases

Answer 1

carbon dioxide, water vapour and methane

Question 2

describe the greenhouse effect

Answer 2

electromagnetic radiation from the sun reaches the earth and is absorbed by land and sea, some radiation is re-emitted as infrared
greenhouse gases absorb this radiation and emit it back towards the Earth

Question 3

infrared radiation causes covalent bonds to

Answer 3

vibrate more and absorb energy

Question 4

what dos IR spectroscopy do

Answer 4

uses infrared radiation to increase the vibrational energy of covalent bonds in a sample

Question 5

what determines the frequency of infrared radiation absorbed by a covalent bond

Answer 5

the atoms either side of the bond and the position of the bond in the molecule

Question 6

what is fragmentation

Answer 6

when molecules break up when they are bombarded with high energy electrons

Question 7

what are some uses of infrared spectroscopy

Answer 7

breathalysers and emissions monitoring

Question 8

how do you identify an unknown compound using both infrared spectroscopy and mass spectrometry

Answer 8

molecular formula
functional groups
structure

Question 9

draw the setup for a reflux reaction and label it

Question 10

why do we use reflux reactions

Answer 10

to heat volatile liquids

Question 11

why do we use distillation reactions

Answer 11

to separate substances with different boiling points

Question 12

draw the set up for a distillation

Question 13

when would you use redistillation

Answer 13

purify volatile substances

Question 13

how would you purify an organic liquid

Answer 13

separation funnel to remove organic layer from aqueous layer
use drying salt like anhydrous calcium chloride
redistill

Question 14

give the functional group, properties and reaction of alkanes

Answer 14

C-C
unreactive and non polar
undergo radical substitution

Question 15

give the functional group, properties and reaction of alkenes

Answer 15

C=C
non polar and electron rich double bond
undergo electrophilic substitution

Question 16

give the functional group, properties and reaction of alcohols

Answer 16

C-OH
polar C-O bond
undergo nucleophilic substitution and elimination

Question 17

give the functional group, properties and reaction of haloalkanes

Answer 17

C-X
polar C-X bond
undergo nucleophilic substitution

Question 18

give the functional group, properties and reaction of carboxylic acids

Answer 18

-COOH
- carbon electron deficient