Organics Level 3

Question 1

What products are produced when primary alcohols are oxidised?

Answer 1

Aldehydes and with a sufficient/ strong enough oxidising agent, will produce carboxylic acid

Question 2

What is produced when secondary alcohols are oxidised

Answer 2

Ketones

Question 3

Can tertiary alcohols be oxidised?

Answer 3

No, do not readily react with oxidising agents

Question 4

Aldehydes

Answer 4

Suffix: “anal” e.g. butanal, ethanal

Functional group -RCH=O

Question 5

Ketones

Answer 5

Suffix: “anone” e.g. butanone

Functional group -RC=OR

Question 6

Observations when using acidified potassium dichromate

Answer 6

is reduced, forms Cr 3+ ion and colour change from orange to green

Question 7

Observations when using acidified potassium permanganate

Answer 7

reduced, colour change from purple to colourless. Forms Mn 2+ ions

Question 8

Examples of weak oxidants and what can they oxidise

Answer 8

Tollen’s reagent. Benedicts solution and Fehlings solution

• only able to oxidise aldehydes into corresponding carboxylic acid
• cannot oxidise primary and secondary alcohols

Question 9

Tollen’s reagent observations

Answer 9

• produced fresh

- colour change from colourless to silver, a silver mirror will form on test tube’s wall.

Question 10

Benedict’s solution observations

Answer 10

• colour change from blue to brick red copper precipitate

- Cu 2+ ions reduced to Cu + ions.

Question 11

Fehling’s solution observations

Answer 11

• formed by mixing Fehling’s A and B solutions together.
• Cu 2+ reduced to Cu +
• colour change from blue to brick red.

Question 12

Acid Chlorides and formation

Answer 12

Suffix -oyl chloride e.g. ethanoyl chloride
Functional group -C=OCl
Replace OH group from carboxylic acid with Cl in a substitution reaction, catalyst SOCl2 is required

Question 13

Amides

Answer 13

Suffix: anamide
Functional group -C=ONH2
Substitute Cl group from acyl chloride with NH2
-catalyst NH3 and heat is required

Question 14

Esters

Answer 14

Functional group -C=OO
-prepared by esterification
-produced when alcohol and carboxylic acid reacts together or alcohol and acyl chlorides
-catalyst conc H2SO4 and heat is required
Prefix of alcohol chain then -yl and prefix of carboxylic chain then -anoate.
-fruity odours.

Question 15

chiral molecules

Question 16

enantiomers

Answer 16

• a chiral molecule and its non-superimposable mirror image
• contains asymmetrical carbon where carbon is attached to 4 different groups.
• can be distinguished because they rotate plane polarised light in opposite directions.

Question 17

carboxylate ion

Answer 17

• a basic ion of the corresponding carboxylic acid e.g. ethanoate ion
• carboxylic acid without the H from the hydroxyl group.
• -1 charge

Question 18

Acid chlorides to carboxylic acids

Answer 18

• add water
• substitution reaction where Cl is substituted with OH group from water.
• other product is HCl as steamy fumes turn blue litmus red
• extremely vigorous reaction

Question 19

polyesters (condensation polymerisation)

Answer 19

carboxylic acid monomers joining with complimentary alcoholic monomer to form ester linkages. therefore forms polymers called polyesters.

Question 20

polyamides (condensation polymerisation)

Answer 20

Carboxylic acid monomers join with complimentary amine monomer to form amide linkages. therefore forms polymers called polyamides.

Question 21

Ester properties

Answer 21

• Not soluble in water other than methyl methanoate.
• Neutral
• complete

Question 22

alcohols with acid chlorides

Answer 22

• produces ester

- reaction is esterification

Question 23

Copper sulfate

Answer 23

-reacts with ammonia and amines to give a deep blue copper complex which is soluble in water.

Question 24

Amide properties

Answer 24

-complete

Question 25

Aldehydes and ketone properties

Answer 25

-complete

Question 26

Hydrolysis

Answer 26

- adding water to to break large molecule into two smaller molecules. - Dilute acid or base is required as a catalyst. - Heat required to speed up reaction

Question 27

Separating funnel

Answer 27

- separates compounds based on solubility. - more dense bottom layer can be run off. - e.g. separates ester and water where esters are insoluble in water.

Question 28

Distillation

Answer 28

- separating a product from reactants with a different boiling point - separated gas then travels through a condensing tube which condenses the gas into a liquid that can be collected. - e.g to get aldehydes from primary alcohols

Question 29

Fractional distillation

Answer 29

-a much accurate and slower from of normal distillation

Question 30

Filtration

Answer 30

-removing solids from liquids

Question 31

Reflux

Answer 31

- speeds up or causes organics reactions to occur without losing volatile compounds when they evaporate. - when heat is used to increase rate of reaction, compounds evaporate however, cold water condensation tube turns gas back into liquid, falling back down and continue to react. - e.g acid or base hydrolysis of an ester