Alcohols

Question 1

What are alcohols?

Answer 1

Organic compounds that contain one or more hydroxyl functional groups attached to a carbon atom

Question 2

Classes of alcohol

Answer 2

Aromatic

Aliphatic

Question 3

Difference between aromatic and aliphatic alcohol

Answer 3

Aliphatic have OH group attached to straight chain carbon, aromatic have OH group attached to benzene ring

Question 4

The most widely used alcohols are

Answer 4

Methanol
Ethanol
2-propanol

Question 5

Classes of aromatic alcohols

Answer 5

Primary
Secondary
Tertiary

Question 6

Methanol use

Answer 6

Antifreeze
Dry gas

Both automotive products

Question 7

Ethanol use

Answer 7

Solvent for drugs and chemicals

Question 8

2-propanol use

Answer 8

Antiseptic

Question 9

Phenols are…

Answer 9

The simplest form of aromatic alcohols

Question 10

Difference between phenol and aliphatic alcohol

Answer 10

More acidic
Toxic
Causes skin burns

Question 11

Uses of phenol derivative, thymol

Answer 11

To kill fungi and hookworms

Question 12

One of the big differences between alcohols and hydrocarbons is…

Answer 12

Their ability to give and receive H bonds.

Question 13

Effect of H bonds on alcohols

Answer 13

It increases the intermolecular force and therefore the mp and bp. It also allows them dissolve in water.

Question 14

Tests for alchols

Answer 14

Sodium test
Iodoform reaction
Phenol test
Jones’ oxidation reaction
Lucas test

Question 15

Sodium test for alcohol

Answer 15

Rapid evolution of H gas

Question 16

Iodoform test for alcohol

Answer 16

Test is positive for a few specific secondary alcohols that contain at least, one methyl group in the alpha position.

Question 17

Mechanism of iodoform test

Answer 17

When iodine and sodium hydroxide are added to a compound that contains either a methyl ketone or a secondary alcohol, a pale yellow precipitate of iodoform or triiodomethane is formed.

Question 18

How is the reagent for iodoform test obtained?

Answer 18

Iodine + NaOH

Question 19

Iodoform test is also used to test for…

Answer 19

Methyl ketone

Question 20

The only primary alcohol that gives positive iodoform test is…

Answer 20

Ethanol

Question 21

What makes up Lucas reagent?

Answer 21

ZnCl2 in concentrated HCl

Question 22

The Lucas test is based on…

Answer 22

The rate of reaction of alcohols to give alkyl halides

Question 23

The reaction that occurs in the Lucas test can be seen as a

Answer 23

nucleophilic substitution reaction.

Question 24

The observation of a change where the clear and colourless characteristic of the solution changes to a turbid, cloudy, and hazy one with Lucas test implies that

Answer 24

a chloroalkane has formed

Question 25

Positive Lucas test is symbolized by...

Answer 25

White turbid, cloudy solution from colorless

Question 26

Tertiary alcohol with Lucas test

Answer 26

They react the fastest due to the fact the organic chloride has relatively low solubility in the aqueous mixture.

Question 27

Primary alcohol with Lucas test

Answer 27

The solution remains colourless unless it is subjected to heat. The solution forms an oily layer when heated

Question 28

Secondary alcohol with Lucas test

Answer 28

The solution turns turbid and forms an oily layer in three to five minutes (varies based on the solubility)

Question 29

Positive test for phenol is seen in...

Answer 29

Formation of a blue, violet, purple, green, or red-brown color upon addition of aqueous ferric chloride.

Question 30

Cresol colour in phenol test

Answer 30

Blue

Question 31

Beta naphthol colour in phenol test

Answer 31

Light green

Question 32

Alpha naphthol colour in phenol test

Answer 32

Green

Question 33

Hydroquinine colour in phenol test

Answer 33

Blue

Question 34

Phenol colour in phenol test

Answer 34

Violet or purple

Question 35

What is the colour of ferric chloride?

Answer 35

Yellow-orange

Question 36

What makes up Jones reagent?

Answer 36

Chromic anhydride and dilute sulfuric acid (CrO3 + H2SO4 + H2O) in acetone

Question 37

Positive Jones’ test for primary alcohol

Answer 37

Initially oxidized to aldehydes, then to carboxylic acids

Question 38

Positive Jones’ test for secondary alcohol

Answer 38

The secondary alcohols are oxidized to corresponding ketones

Question 39

Positive Jones’ test for tertiary alcohol

Answer 39

Not oxidized, no reaction

Question 40

Positive Jones’ test for phenol

Answer 40

Oxidation to non-descriptive brown tarry mass

Question 41

The reaction of an alcohol with sodium produces...

Answer 41

Sodium ethoxide and hydrogen gas

Question 42

Relationship between alcohol acidity and reactivity with Na

Answer 42

The more acidic the alcohol, the faster the reaction

Question 43

Which alcohol class is most acidic?

Answer 43

Primary, due to increased electron density on oxygen atom and stearic hindrance

Question 44

Propan-1-ol

Answer 44

Monohydric, secondary aliphatic

Question 45

2-methylbutan-2-ol

Answer 45

Monohydric, tertiary aliphatic

Question 46

2-methylpropanol

Answer 46

Monohydric, primary

Question 47

2-methylphenol

Answer 47

Aromatic/Phenolic

Question 48

Pentan-2-ol

Answer 48

Monohydric, secondary aliphatic