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Flashcards in Organic Tests and reaction Deck (35)
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1
Q

Test for phenolic compounds / phenol

A

Add aqueous iron III chloride-

Purple colour or solution present

2
Q

Test for a carboxylic acid

A

Add sodium carbonate

Fizzing seen with co2 (bubbles))

3
Q

Test for an alcohol

A

I2/ NaOH (aq)
CH3CHOH group
Yellow PPT
Antiseptic smell

4
Q

Test for an aldehyde x2

A

Tollens (AgNO3/NH3 complex)
Silver mirror result

Fehlings (CuSO4 complex) - blue to red colour change result

Both redox

5
Q

Test for aldehydes and ketones

A

24DNP- orange crystals with high melting points (NUCLEOPHILIC addition/elimination)

I2/NaOH A -CH3CO group yellow ppt anti septic smell

6
Q

Distinguishing between aliphatic and aromatic amines

A

1- add nitrous acid to both in cold conditions
Bubbles nitrogen gas seen with aliphatic, no bubbles with aromatic

2- add nitrous acid to both in cold alkaline conditions, add an aromatic compound eg phenol. A colour is produced with aromatic, no colour with aliphatic

7
Q

Identifying an ester

A

Hydrolysis reaction- forms a carboxylic acid (and alcohol) in the form of a colourless solution (aliphatic ester) or White PPT (aromatic )

8
Q

Identifying a basic compound

A

Red litmus paper- turns blue

9
Q

Identifying an acidic compound

A

Turns blue litmus paper red

10
Q

Identifying an amide or nitrile

A

Alkane hydrolysis- produce ammonia NH3 gas that turns red litmus blue

11
Q

Distinguishing between aromatic and aliphatic acids

A

Their solubility in. Water- aliphatic acids are soluble so produce a colourless soliton (no white ppt)

Aromatic acids produce white ppt (insoluble/sparingly)

12
Q

Nitrating benzene

A

Concentrated sulfuric and nitric acid 55degrees

13
Q

Halogenising benzene

A

No light; room temp: anhydrous

14
Q

Alkylation of benzene

A

Room temp , anhydrous

15
Q

Delocalisation energy calculation of benzene

A

Calculate delta H
One is experimental, one is theoretical

The difference between them is the DE

16
Q

If aqueous sodium borohydride is used to reduce Unknown compounds at room temp: what are they going to be?

A

Aldehydes or ketones because it only reduces these

17
Q

Why is phenol more subseptible to Electrophilic substitution (addition of bromine/bromine water)

A

Catalyst isn’t required
Conc bromine not required
Mono subsituted product not produced

18
Q

Production of an aromatic ester from phenol

A

Reaction with ethanoyl chloride - NUCLEOPHILIC substitution

19
Q

Method to identify an aldehyde ketone using DNP

A

1 add unknown to dnp in dilute acid
2- orange crystals form
3- filter and wash with cold solvent
4- dry and take the MP and compare with literature value

20
Q

Oxidation reactions reagent and observation

A

Acidification potassium dichromate (aqueous sulfuric acid used)

Orange to green colour change

Not with ketones though as they’re not easily oxidised

21
Q

What is produced in the hydrolysis of acid chlorides

A

Carboxylic acid

22
Q

Is the sodium salt for benzoicacid soluble?

A

Yes

23
Q

How do you obtain a carboxylic acid from salt?

A

Add strong acid

24
Q

How do you isolate a product eg carboxylic acid?

A

Filter
Wash with cold solvent
Recrystallise from hot water
Dry in oven below MP

25
Q

Converting carboxylic acid to amide

A

Add ammonium carbonate o acid to produce ammonium salt

Heat salt and this forms an amide

26
Q

Converting carboxylic acid to nitrile

A

Add ammonium carbonate to acid and produces ammonium salt

Heat salt to form an amide

Add phosphorus V oxide (P4O10) amide dehydrates to form nitrile

27
Q

Converting amide to nitrile

A

Add phosphorus V oxide (P4O10) and it dehydrates to form nitrile

28
Q

Converting nitrile to carboxylic acid

A

Hydrolysis - acid – reflux with hydrochloric acid aq and forms a C acid

29
Q

Converting nitrile to amine

A

Lithium aluminium hydride (reduction) room temp, anhydrous [4H]

30
Q

Converting halogenoalkane to :
Nitrile
Amine

A

Nitrile- reflux with potassium cyanide in a solution of ethanol (NUCLEOPHILIC sub)

Amine: Heat Halo with excess ammonia in a solution of ethanol
Conducted in a sealed tune immersed in boiling water
NUCLEOPHILIC sub

31
Q

How to form an aromatic amine eg phenylamine?

A

Heat nitrobenzene with tin and hydrochloric acid - reduction
This forms a soluble salt, then add sodium hydroxide (aq) to form aromatic amine

(Use steam distillation to separate phenylamine from nitroB)

32
Q

Forming an aromatic ester from phenol

A

Add ethanoyl chloride : of produces ester - NUCLEOPHILIC sub

33
Q

Tests for phenol

A

1- aqueous iron III chloride
Purple colour seen (OH)

2- bromine / bromine water- White PPT subsitutes 2,,4,6 positions (Electrophilic substitution)

34
Q

Forming an alkene from an alcohol

A

Dehydration : excess concentrated sulfuric acid, 180degrees and reflux

35
Q

Formation of an alcohol from an alkene

A

Hydration - phosphoric acid catalyst 300degrees 70atm

Steam