Synthetic Routes

Question 1

What kind of reaction occurs to turn an alkane to an alkene?

Answer 1

Cracking

Question 2

What type of reaction turns an Alkane to a haloalkane?

Answer 2

Radical substitution

Question 3

What type of reaction turns and alkene into a haloalkane?

Answer 3

Halogenation

Question 4

What type of reaction turns an alkene into a polymer?

Answer 4

Addition polymerisation

Question 5

What type of reaction turns an alkene into an alcohol?

Answer 5

Hydrolysis

Question 6

What type of reaction turns an alcohol to an alkene?

Answer 6

Dehydration

Question 7

What type of reaction turns an alcohol into:

An aldehyde

A ketone

A carboxylic acid

Answer 7

Oxidation of primary alcohol goes to an aldehyde

Oxidation under reflux of a primary alcohol goes to a carboxylic acid

Oxidation of a secondary alcohol goes to a ketone

Tertiary alcohols do not oxidise easily

Question 8

What type of reaction turns an alcohol to a haloalkane?

Answer 8

Substitution

Question 9

What type of reaction turns a haloalkane into an alcohol?

Answer 9

Hydrolysis

Question 10

What are the reaction conditions to turn an alkane to a haloalkane?

Answer 10

Cl2

U.V light

Free radical substitution

Question 11

What are the reaction conditions for the synthesis of primary amines from haloalkanes?

Answer 11

Ammonia

Heating

Question 12

What are the reaction conditions for the synthesis of secondary and tertiary amines and ammonium salts from haloalkanes?

Answer 12

Ammonia

Heating

Question 13

What are the reaction conditions for the synthesis of nitriles from haloalkanes?

Answer 13

KCN (potassium cyanide)

Ethanol

Reflux

Question 14

What are the reaction conditions to synthesise a primary amine from a nitrile?

Answer 14

LiAlH4 with dilute H2SO4

In dry ether

Question 15

What are the reaction conditions for the synthesis of an alkene from a haloalkane?

Answer 15

NaOH

Ethanol

Reflux

Question 16

What are the reaction conditions for the synthesis of a haloalkane from an alkene?

Answer 16

HBr (hydrogen bromide)

Room temperature

Question 17

What are the reaction conditions for the synthesis of dibromoalkane from an alkene?

Answer 17

Br2

Room temperature

This is the test for unsaturation of hydrocarbons

Question 18

What are the reaction conditions for the synthesis of an alcohol from a haloalkane?

Answer 18

Warm NAOH

Reflux

Question 19

What are the reaction conditions for the synthesis of an alcohol form an alkene?

Answer 19

H3PO4 catalyst

Steam

300 degrees

60 atm

Or

H2O

H2SO4 catalyst

Question 20

What are the reaction conditions for the synthesis of an alkene from an alcohol?

Answer 20

Conc H2SO4

Reflux

Question 21

What are the reaction conditions to synthesis of an aldehyde from an alcohol?

Answer 21

Primary alcohol

K2Cr2O7/H2SO4

Heat in distillation apparatus

Question 22

What are the reaction conditions for the synthesis of a ketone from an alcohol?

Answer 22

Secondary alcohol

K2Cr2O7/H2SO4

Reflux

Question 23

What are the reaction conditions for the synthesis of a carboxylic acid from an alcohol?

Answer 23

Primary alcohol

K2Cr2O7/H2SO4

Reflux

Question 24

What are the reaction conditions for the synthesis of a carboxylic acid from an aldehyde?

Answer 24

K2Cr2O7/H2SO4

Reflux

Question 25

What are the reaction conditions for the synthesis of of an alcohol from an aldehyde/ketone?

Answer 25

NaBH4 in water With methanol

Question 26

What are the reaction conditions for the synthesis of an Ester from a carboxylic acid?

Answer 26

Alcohol Conc H2SO4 catalyst Heat

Question 27

What are the reaction conditions for the synthesis of a carboxylic acid from an Ester?

Answer 27

H2O Dilute H2SO4 catalyst Reflux Or Dilute NaOH Reflux

Question 28

What are the reaction conditions for the synthesis of a hydroxynitrile from an aldehyde/ketone?

Answer 28

KCN or HCN H2SO4 Room temperature

Question 29

What are the reaction conditions to synthesise a carboxylic acid from an acyl chloride?

Answer 29

H2O Room temperature

Question 30

What are the reaction conditions for the synthesis of an Ester from an acyl chloride?

Answer 30

Alcohol Room temperature

Question 31

What are the reaction conditions for the synthesis of a primary amide from an acyl chloride?

Answer 31

Ammonia Room temperature

Question 32

What are the reaction conditions for the synthesis of an N-substituted amide from an acyl chloride?

Answer 32

Amine Room temperature

Question 33

How do acid anhydrides react?

Answer 33

In the same way as acyl chlorides

Question 34

What are the reaction conditions for the synthesis of nitro benzene from benzene?

Answer 34

Conc H2SO4 Conc HNO3 Below 55 degrees

Question 35

What are the reaction conditions for the synthesis of a phenyl ketone from benzene?

Answer 35

Acylation reaction RCOCl acyl chloride AlCl3 catalyst Reflux Non aqueous environment

Question 36

What are the reaction conditions for the synthesis of an aromatic amine from nitro benzene?

Answer 36

Sn (Tin) Conc HCl Reflux Reduction reaction

Question 37

What are the reaction conditions for the synthesis of an N-Phenylethanamide from an aromatic amine?

Answer 37

CH3COCl Acyl chloride Addition elimination reaction

Question 38

What is the test for unsaturation?

Answer 38

Bromine water Shake Bromine water will decolourise if C=C binds are present as bromine is added across the double bond

Question 39

What is the test for haloalkanes?

Answer 39

Silver nitrate Ethanol Water Precipitate forms and is a specific colour depending on the halide present Halogen atom is displaced as a halide ion

Question 40

What is the test for carbonyl groups?

Answer 40

Acidified potassium dichromate Aldehyde changes colour from orange to green and ketones have no colour change Tollens reagent Aldehyde forms a silver mirror Ketone form no silver mirror Fehlings reagent Aldehydes form a dark red precipitate Ketones do not form a precipitate

Question 41

What is the test for carboxylic acids?

Answer 41

Universal indicator pH of a weak acid Reactive metal Effervescence of CO2 gas Metal carbonate Effervescence of a gas

Question 42

What is the test for an alcohol?

Answer 42

Warm with carboxylic acid add a few drops of H2SO4 Sweet smell Forms an Ester

Question 43

How do you identify carboxylic acids?

Answer 43

React with Metals to form a salt and hydrogen Strong bases to form a salt and water Carbonates to form a salt and water and CO2 Alcohols to form an Ester

Question 44

How do you identify esters?

Answer 44

Undergo hydrolysis Acid hydrolysis forms carboxylic acid and alcohol Alkaline hydrolysis forms a carboxylate ion and an alcohol

Question 45

How do you identify alkenes?

Answer 45

Undergo addition reactions Bromine water becomes decolourised Hydrogen halides form haloalkanes Themselves to form addition polymers

Question 46

How do you identify alcohols?

Answer 46

Primary alcohols oxidise to football aldehydes Secondary alcohols oxidise to from ketones Tertiary alcohols do not oxidise

Question 47

How do you identify aldehydes and ketones?

Answer 47

Aldehydes oxidise to carboxylic acids Aldehydes reduce to alcohols Ketones reduce to alcohols

Question 48

How do you identify haloalkanes?

Answer 48

Ammonia to form amines Reduced by alkaline hydrolysis to form alcohols

Question 49

Why is synthesis important for chemists?

Answer 49

To create particular products from starting materials

Question 50

What steps should you take to determine a synthetic route?

Answer 50

1. Notice all changes taken place between original and final compound 2. Start with one functional group and decide how to synthesise it 3. Draw out this step 4. Calculate how to convert second functional group

Question 51

What is the criteria scientists follow when synthesising compounds?

Answer 51

No solvent Non hazardous starting material Fewest reaction steps High atomic yield