Reactions in chemistry

Question 1

what type of reaction of alkanes forms free radicals

Answer 1

free radical substitution

Question 2

free radical substitution steps

Answer 2

-initiation
-propagation
-termination

Question 3

free radical substitution of methane with chlorine radicals

Answer 3

1. Cl2–> (UV) 2Cl*
2. CH4 + Cl* –> CH3* + HCl
3. CH3* + Cl2 –> CH3Cl + Cl*
4. CH3* + CH3* –> C2H6
5. CH3* + Cl* –> CH3Cl
6. Cl* + Cl* –> Cl2

Question 4

complete combustion of alkanes form

Answer 4

CO2 + H2O

Question 5

incomplete combustion of alkanes form

Answer 5

H2O + CO + C

Question 6

reforming of alkanes form

Answer 6

branched-chain alkanes and cyclic hydrocarbons

Question 7

conditions for reforming

Answer 7

catalyst (platinum stuck on aluminium oxide)

Question 8

cracking of alkanes form

Answer 8

alkene + shorter chained alkane

Question 9

What process forms polymers from alkenes

Answer 9

addition polymerisation

Question 10

what type of reaction forms alcohols from alkenes

Answer 10

addition reactions (steam hydration)

Question 11

conditions for formation of alcohols from alkenes

Answer 11

• steam
• H3PO4 (s) (Phosphoric (V) acid catalyst)
• 300 degrees celcius
• 60 atm pressure

Question 12

what type of reaction forms haloalkanes from alkenes

Answer 12

addition

Question 13

alkene + hydrogen halide reaction mechanism + type of reaction

Answer 13

addition

Question 14

alkene + halide reaction mechanism + type of reaction

Answer 14

electrophilic addition

Question 15

what does oxidation of alkenes form

Answer 15

a diol

Question 15

conditions for oxidation of alkenes

Answer 15

• acidified potassium manganate

Question 16

product of oxidation of ethene + colour change

Answer 16

ethane-1,2-diol (purple-colourless)

Question 17

conditions for formation of alkene from alcohol

Answer 17

• H3PO4 (s)
• dry conditions + heat

Question 18

conditions for reaction of haloalkane with cyanide

Answer 18

• potassium cyanide
• ethanolic
  -reflux

Question 19

reaction mechanism for haloalkane + cyanide + type of reaction

Answer 19

nucleophilic substitution

Question 20

reaction mechanism for haloalkane + ammonia + type of reaction

Answer 20

nucleophilic subsititution

Question 21

conditions for reaction of haloalkane with ammonia

Answer 21

• warm
• excess ethanolic ammonia

Question 22

conditions for nucleophilic substitution reaction of haloalkane with OH-

Answer 22

• NaOH/KOH(aq)
  -warm under reflux

Question 23

conditions for elimination reaction of haloalkane with OH-

Answer 23

• ethanolic KOH
• warm
• reflux

Question 24

reaction mechanism of haloalkane + ethanolic OH + what the OH acts as

Answer 24

a base

Question 25

Oxidation of primary alcohols

Answer 25

aldehyde- carboxylic acid

Question 26

primary alcohol- aldehyde conditions

Answer 26

• distillation
• acidified K2CrO7

Question 27

primary alcohol- carboxylic acid conditions

Answer 27

• reflux
• acidified K2Cr2O7

Question 28

oxidation of secondary alcohols

Answer 28

ketone

Question 29

secondary alcohol-ketone conditions

Answer 29

• reflux
• acidified K2Cr2O7

Question 30

reduction of aldehyde

Answer 30

primary alcohol

Question 31

aldehyde- primary alcohol conditions

Answer 31

• reduction
• LiAlH4 in dry ether

Question 32

reduction of ketone

Answer 32

secondary alcohol

Question 33

ketone- secondary alcohol conditions

Answer 33

• reduction
• LiAlH4 in dry ether