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Flashcards in 4.2 Deck (21)
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1

alchohol general formulae

CnH2n+1OH

2

boiling point of alcohols

increases as chain length increases, is higher than that of alkenes due to hydrogen bonding

3

impact of branching on boiling point

branching reduces boiling point due to reduced surface contact

4

solubility in water of alcohols vs alkenes

alkenes insoluble in water, alcohols are soluble in water because they are polar and from hydrogen bonds

5

primary alcohol

OH group is attached to a carbon that is attached to one other carbon / has 2 hydrogens attached to it

6

secondary alcohol

OH group is attaches to a carbon that is attached to 2 other carbons / has one hydrogen attached to it

7

tertiary alcohol

OH group is attached to a carbon that is attached to 3 other carbons / has no hydrogens attached

8

what is used to oxidise alcohols

potassium dichromate shown as K2Cr2O7 / H2SO4 or Cr2O7 ^-2 / H^+

9

what does potassium dichromate look like

orange solution that turns green when reduced

10

oxidation of tertiary alcohols

not oxidised under these contidions, for it to oxidise the C the OH is attached to must have a H

11

oxidation of secondary alcohols

oxidise to form keytones

12

ketones

functional group C=O not at the end of the chain, names end in -one

13

oxidation of primary alcohols

oxidise once to from aldehydes under distillation and can oxidise further to form carboxylic acids under reflux

14

aldehydes

C=OH functional group at the end of the chain end in -anal

15

alcohols into alkenes and back

H2O can be removed from alcohols in the presence of heat and a H3PO catalyst. The OH is removed from one carbon and the H from the adjacent carbon forming a c=c bond

16

alcohols into haloalkanes

the OH group can be substituted for a halide ion in the presence of a halide salt solution and acid catalyst

17

nucleophylic substitution

the halo-carbon bond becomes polar leaving it open to attack by nucleophiles. The nucleophile uses its Lone pair to provide the electrons for a new bond displacing the halogen

18

nucleophile

electron pair donor - will probably have a lone pair

19

problems with CFCs / haloalkanes

in the atmosphere the halogen radical will react with ozone to from a halogen oxygen radical that reacts further with ozone. overall reaction O3 + O -> 2 O2

20

infrared spectroscopy

works by firing IR radiation at a compound. Different bonds absorb different amounts and frequencies of IR radiation. Looking at the absorption spectra allows you to identify the bonds in compounds

21

stages of spectroscopy

vaporisation, ionisation, acceleration, deflection, detection