halo alkanes and haloarenes

Question 1

alchohol with hcl

Answer 1

in the presense of ZnCl2 we get R-CL + H2O

Question 2

mixture of conc HCl and anhyd ZnCL2 is

Answer 2

lucas reagent

Question 3

3 degree alcohol with HCl

Answer 3

R-Cl +H2O without the presence of ZnCL2

Question 4

alcohol with HBr

Answer 4

in the presence of NaBR + H2SO4 because HBr is not readily available product is R-Br + H2O

Question 5

alcohol with HI

Answer 5

in the presence of KI + 95% h3PO4 gives R-I + H2O

Question 6

alcohol reaction with PCl3

Answer 6

3R-OH + PCl3 gives 3R-Cl + H3PO3(phosporic acid)

Question 7

alcohol reaction with PCl5

Answer 7

R-OH + PCl5 gives R-CL + HCl + POCl3

Question 8

why do we not use PBr3 and PI3

Answer 8

they are very unstable compounds

Question 9

alcohol reaction with SOCl2

Answer 9

R-Cl + SO2 gas + HCl gas

Question 10

why do we not use SOBr and SOI

Answer 10

they are very unstable compounds

Question 11

why do we not do fluorination

Answer 11

the F-F bond in F2 is very strong it needs alot of energy to break the bond by giving huge amount of energy to break it will release huge amount of energy when it breaks which will cause and exothermic reaction which is uncontrolable therefore fluorine is not preferred

Question 12

chlorination and bromination takes place in the presence of

Answer 12

UV light

Question 13

why do we not use iodisation

Answer 13

this process is very slow and reversible so its not preferred

Question 14

why do we not do chlorination and bromination

Answer 14

it forms mixtures of poly haloalkanes which is very difficult to seperate

Question 15

reaction with symmetrical alkene and H-X

Answer 15

incase of symmetrical alkane the halogen can go to any one of the carbon atom and the hydrogen will go to the other carbon atom which is left out

Question 16

reaction with asymmetrical alkene and H-X

Answer 16

markovnikovs rule will take place

Question 17

reaction with assymetrical alkene and HBr in presence of peroxide

Answer 17

anti markovnikovs rules will take place

Question 18

by adding halogens to alkenes

Answer 18

always forms dihalide alkanes (colorless)

Question 19

halogen exchange reactions

Answer 19

finkelsteins and swartz

Question 20

finkelstein reaction

Answer 20

R-Cl or R-Br with NaI in dry acetone gives R-I + NaBr or NaCl

Question 21

swartz reaction

Answer 21

only with fluorine
R-Cl or R-Br + AgF/Hg2F2/SbF3/COF2 gives R-F + AgBr/AgCl….

Question 22

What is Lewis acid

Answer 22

electrophilic substitution we need an electrophile, this lewis acid will help to produce and electrophile. This is doen by accepting electrons from any molecule

Question 23

example of lewis acid

Answer 23

FeCl3

Question 24

toluene + Cl2

Answer 24

in the presence of FeCl3 it gives o-chlorotoluene and p-chlorotoluene

Question 25

why is it easy to seperate mixture of o-chlorotoluene and p-chlorotoluene

Answer 25

it is easy because they both have different boiling points

Question 26

why should we make chlorotoluene in the dark

Answer 26

because in the presence of sunlight/UV light it will form benzylchloride

Question 27

making of diazonium salt

Answer 27

only 1 degree amines can make diazonium salt

Question 28

preparation of diazonium salt

Answer 28

1 degree aniline in the presence of NaNO2 and HNO2 gives benzene diazonium salt

Question 29

nucleophilic substitution with KCN and AgCN

Answer 29

when its KCN the carbon will form the bond when its AgCN nitro group will form the bond

Question 30

example of chiral compounds

Answer 30

lactic acid, 2-bromobutane,2-butanol

Question 31

example of racimic mixture

Answer 31

butan-2-ol

Question 32

beta elimination forms?

Answer 32

alkenes when R-X is reacted with alc KOH under heat

Question 33

when R-X reacts with alc KOH

Answer 33

it forms ALKENES

Question 34

wurtz reaction

Answer 34

2R-X + 2Na in the presence of dry ether gives R-R + 2NaX

Question 35

why do we use dry ether and not water in wurtz reaction

Answer 35

because water will react with sodium which is highly explosive

Question 36

grignards reagent

Answer 36

R-Mg-X

Question 37

grignard reagent + H2O

Answer 37

gives alkanes