reaction pathways and synthetic routes

Question 1

reaction which turns alkane into alkene.

Answer 1

cracking
1)450 C, 70atm thermal,
2)1-2atm catalytic + aluminium oxide and silicon dioxide

Question 2

reaction and conditions which turns alkene into alkane.

Answer 2

hydrogenation reaction. nickel catalyst, 150 degrees Celsius (Ni/H2)

Question 3

reaction which turns alkene to polymer

Answer 3

addition polymerisation, high temperature and pressure

Question 4

reaction for alkene to alcohol

Answer 4

hydration, requires H3PO4, H2O, 300 degrees C, at 65 atm

Question 5

reaction for alcohol to alkene

Answer 5

dehydration, H2SO4, 170 degrees

Question 6

reaction for alkene to haloalkane

Answer 6

halogenation (hydrogen halide)

Question 7

reaction for alkane to haloalkane

Answer 7

free radical substitution, UV light or temp above 300C

Question 8

reaction for haloalkanes to alcohols

Answer 8

hydrolysis, requires a nucleophile present, nucleophilic substitution (NaOH)

Question 9

reaction for alcohol to haloalkane

Answer 9

halide substitution, H3PO4, sodium halide

Question 10

reaction for alcohol to aldehyde

Answer 10

oxidation (distillation) K2Cr2O7, H2SO4, ONLY PRIMARY ALCOHOLS

Question 10

reaction for alcohol to ketone

Answer 10

oxidation (distillation), K2Cr2O7, H2SO4 ONLY SENCONDARY ALCOHOLS

Question 11

reaction for alcohol to carboxylic acid

Answer 11

oxidation (reflux), K2Cr2O7, H2SO4, ONLY PRIMARY ALCOHOL

Question 12

reaction for carboxylic acid to ester

Answer 12

esterification, H2SO4, 80C

Question 13

test for unsaturated hydrocarbons and observations

Answer 13

bromine water and shake, turns mixture colourless

Question 14

test for haloalkane and observations

Answer 14

silver nitrate, ethanol and water, white, cream and yellow precipitates

Question 15

test for carbonyl and observations

Answer 15

1) acidified potassium dichromate- ketones no change - aldehydes orange to green
2) Fehling’s solution- ketones no change - aldehydes dark red precipitate
3) Tollens’ reagent- ketones no silver mirror - aldehydes silver mirror

Question 16

test for carboxylic acid and observations

Answer 16

1) universal indicator - pH of weak acid
2) reactive metal - effervescence (H2)
3) metal carbonate - effervescence (CO2)

Question 17

test for alcohol and observations

Answer 17

warm with carboxylic acid and some H2SO4 - sweet ester aroma

Question 18

what is an aromatic compound?

Answer 18

a compound with at least one benzene ring in the structure

Question 19

what is an aliphatic compound?

Answer 19

a compound with a straight chain of carbons or branched straight chain of carbons

Question 20

what is an alicyclic compound?

Answer 20

a compound joined in a ring structure with no benzene rings

Question 21

what is an aldehyde?

Answer 21

double C=O bond on the final carbon in a chain

Question 22

what is a ketone?

Answer 22

double C=O bond on a mid chain carbon (secondary, tertiary)

Question 23

what are standard conditions?

Answer 23

298K (25C), 100KPa

Question 24

reaction for aldehyde OR ketone to alcohol

Answer 24

NaBH4

Question 25

how do you convert between Kelvin and Celsius?

Answer 25

add or subtract 273