ALKYL HALIDES

Question 1

reactivity of alcohol w halogen follows the trend?

Answer 1

I>Br>Cl

Question 1

PREP OF Alkyl halide

Answer 1

react alcohol with hydrogen halide

react alcohol w halogenated agents (PCl3, PBr3, PI3)

by halogenation of alkane

Question 2

which halogenated agent mostly used due to easy availibility

Answer 2

phosphorous trichloride (PCl3)

Question 3

whats the preferred method of making alkyl halide

Answer 3

react alcohol with thionyl halide (SOX2)

Question 4

what catalyst used in preferred methods of prep alkyl halide

Answer 4

pyridine catalyast

Question 5

alkyl halide undergoes nucleopghilic subs reaction due to

Answer 5

bcs the halogen takes away electrons and makes the carbon electrophilic (+) due to which an nucleophile can attack

Question 6

alkyl halide can undergo elimination why

Answer 6

bcs the halogen takes away electron density frm beta hyderogen which makes that H acidic and the elimination reqction can occcur

Question 7

in nucleophile subs reaction the nucleophile attacks whom and kicks out whom?

Answer 7

attacks the carbon and kicks out the halogen of that carbon

Question 8

SN1 mechanism is? , no of steps, what intermediate formed?

Answer 8

unimolecular bi step, 2 steps, carbocation formed,

Question 9

what happen in 1 and 2 step, speed of each step, which is rate determining step

Answer 9

1 step the halogen is removed forming a carbocation 2 step the n.phile attacks and and forms product. 1 step is slow and 2 is fast, rate determining is 1 step.

Question 10

SN1 occurs easily in? and why. order of kinetics in SN1 and means

Answer 10

occur easily in tertiary alkyl halides bcs the carbocation can be stabilize easily. first order kinetics means rate of reac depend on the substrate only

Question 11

SN2 mechanism is? , no of steps,

Answer 11

bimolecular uni step, 1 reaction

Question 12

what happen in step of SN2,

Answer 12

the n.phile attack and halogen leaves in single step. no carbocation formed.

Question 13

SN2 occurs easily in? and why. order of kinetics in SN2 and means

Answer 13

occurs easily in primary alkyl halides bcs of less hindrance and easy attachment of n.phile. 2nd order kinetics means rate of reaction depend on both the substrate and the n.phile

Question 14

what occurs in elimination reaction?

Answer 14

removal of 2 groups\Atoms
2 3 bond create

Question 15

what happens elimination reaction of alkyl halide

Answer 15

removlal of halogen from alpha carbon and removal of hydrogen frm beta carbon

Question 15

what is necessary for elimination reaction to occur

Answer 15

base

Question 16

E1 reaction mechanism is? , no of steps, what intermediate formed?

Answer 16

unimolecular bi step, 2 steps, carbocation formed

Question 17

what happen in 1 and 2 step, speed of each step, which is rate determining step

Answer 17

1 step halogen depart from the carbon and carbocation forms
2 step the base attacks a carbon next to the halogen containing carbon and removes its hydrogen. 1st step is rate deterining

Question 18

order of kinetics in E1 and means

Answer 18

first order kinetics means the rate of reaction depends on the conc of the substrate only

Question 19

E2 mechanism is? , no of steps,

Answer 19

E2 is bimolecular single step reaction, occur in 1 step.

Question 20

what happen in step of E2,

Answer 20

the base attacks the beta carbon and the halogen is extract from alpha carbon together in one step.

Question 21

E2 occurs easily in? and E1 occur easily in?

Answer 21

E2 occur easily in primary alkyl
E1 occur easily in sec or tertiary alkyl halide

Question 22

order of kinetics in E2 and means

Answer 22

2nd order kinetics means the rate of reaction is depend on both the substrate and the attacking base