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Flashcards in Distinguish Test Deck (26):
1

Alkene @bromine

Describe the rest and results

1. Bromine dissolved in CCl4
-> orange-red bromine decolourised


2. Aq. Bromine
-> orange bromine decolourised

2

Alkene @KMnO4

Describe the test and results

1. KMnO4 (aq), NaOH(aq), cold
-> purple KMnO4 decolourised; brown pot MnO2 formed

2. c. KMnO4, H2SO4(aq), warm
-> purple KMnO4 decolourised, light link Mn2+ sol formed

3

Halogenoalkane

NaOH(aq) heat, cool, acidify with HNO3(aq), follow by AgNO3(aq)

->white ppt: chloroalkane
->cream ppt: bromoalkane
->yellow ppt: iodoalkane


RX + NaOH -> ROH + Na+ + X-
Ag+ + X- -> AgX(s)

4

Alcohol@ Na

Na metal

-> eff pxed. Gas evolved "pops" with a lighted splint

5

Alcohol @anhyd. PCl5, SOCl2

-> white fumes of HCl evolved

6

Alcohol @ strong O.A

1. KMnO4(aq) + NaOH(aq), warm
-> purple KMnO4 decolourised, brown ppt Mn2+ formed


2. c.KMnO4, H2SO4(aq), warm
-> purple KMnO4 decolourised, colourless sol Mn2+ formed


3. K2Cr2O7(aq), H2SO4(aq), warm
-> orange K2Cr2O7 turns green

7

Phenol and phenolic cmpd

(3 ways)

1. neutral FeCl3(aq)
-> violet/ purple colouration formed


2. Aq. Bromine
-> orange bromine decolourised, white ppt of 2,4,6-tribromophenol formed


3. Half spatula of Mg powder/ small piece of Na metal
-> eff pxed. Gas evolved "pops" with a lighted splint

8

Alcohol/ carbonyl

OH
|
R-C-CH3
|
H

O
||
R-C-CH3

@tri-iodomethane test

A few drops of NaOH(aq), follow by a few drops of I2(aq), warm

-> yellow ppt of CHI formed

9

Carbonyl cmpd

@2,4-DNPH

-> yellow/ orange ppt formed

10

Tollens' reagent?

Aldehyde
A sol of AgNo3(aq) in Xs NH3(aq), warm

-> silver minor/ grey ppt formed

11

Fehling's reagent?

Alphatic aldehyde

Alkaline sol of Cu2+ and tartrate ion, warm

-> reddish-brown ppt of Cu2O formed

12

Aldehyde @strong O.A

1. KMnO4(aq), NaOH(aq), warm
-> purple KMnO4 decolourised, brown ppt MnO2 formed


2. c.KMnO4, H2SO4(aq), warm
-> purple KMnO4 decolourised, colourless sol Mn2+ formed


3. K2Cr2O7(aq), acidified with H2SO4, warm
-> orange K2Cr2O7 turns green

13

2 ways for carboxylic acid

1. Na2CO3(aq/s)/ NaHCO3(aq/s)
->eff pxed. Gas evolved gives a white pot in limewater


2. small spatula of Mg powder/ small piece Na
-> eff pxed. Gas evolved "pops" with a lighted splint

14

Acid chloride

AgNO3(aq)

-> while fumes of HCl evolved, white ppt of AgCl formed

15

Ester

Dilute mineral acid, reflux;

Carry our distinguishing test in distillate for alcohol

16

Primary amide

NaOH(aq)

-> gas evolved turned moist red litmus paper blue evolved (NH3)

17

Phenylamine

Aq. Bromine

-> orange bromine decolourised, white ppt of 2,4,6-tribromophenylamine formed

18

Aq Br2 can be used for?

1. Alkene
2. Phenol
3. Phenylamine

19

2,4-DNPH for?

Carbonyl cmpd
-aldehyde
-ketone

20

K2Cr2O7

-alcohol (1,2)
-aldehyde

21

Strong OA (KMnO4), heat

Alkene
Methylbenzene
Alcohol(1,2)
Aldehydes

22

Strong OA (KMnO4) cold

Alkene

23

PCl5, PCl3, SOCl2, PBr3

All alcohols

24

Na(s)

All alcohol, phenol, RCOOH

25

Mg(s)

Phenol, RCOOH

26

Na2CO3
NaHCO3

RCOOH
Acid chlorides