EXPERIMENT 8: Properties of Alcohols and Phenols

Alcohols and Phenols

Contain the functional group, hydroxyl.

Alcohols

Are compounds in which one or more hydrogen atoms in an alkane have been replaced by an -OH group.

Alcohols

They contain the -OH (hydroxyl) functional group attached to a saturated carbon.

Phenol

The OH group is connected to a carbon on a benzene ring.

Alcohol

The OH group is connected to a sp3 hybridized carbon atom.

carbon on a benzene ring

Where is the OH group connected in Phenol ?

sp3 hybridized carbon atom

Where is the OH group connected in Alcohol?

Primary (1°)

Secondary(2°)

Tertiary (3°)

Alcohols are classified into three categories:

Primary alcohol

Carbon bearing the -OH has one (1) R- group attached.

Secondary alcohol

Carbon bearing the -OH has two (2) R- groups attached.

Tertiary alcohol

Carbon bearing the -OH has three (3) R- groups attached.

Phenols

Are closely related to alcohols because of the presence of the hydroxyl (-OH) group.

True

Concentrated solutions of the compound phenol are quite toxic and can cause several burns (True / False)

Phenols

Which are more acidic, alcohols or phenols?

Bordwell-Wellman test solution

Contains potassium dichromate dissolved in sulfuric acid.

orange-yellow

What color of solution is the Bordwell-Wellman solution.

The Cr2O7^-2 (dichromate) ion

The orange-yellow color is due to?

chromic (Cr^+3) ion

The oxidation number of chromium in dichromate is reduced to ?

blue-green

What color solution does chromic ion results?

orange-yellow to green

This color change serves as an indicator for the presence of a primary or secondary alcohol.

aldehyde, acid

A primary alcohol is oxidized first to _______, which will be further oxidized to an _____.

Chromic acid

Can also be used to distinguish between types of alcohols by oxidizing the alcohol. (acidified dichromate, an oxidizing agent)

Carboxylic acid

Primary alcohols are oxidized to?

Ketones

Secondary alcohols are oxidized to?

Not oxidized

Are tertiary alcohols (oxidized /not oxidized)?

blue-green

During the oxidation, the orange-yellow color of the chromic acid changes to a ___________ solution.

can be

Phenols (can / cannot) be oxidized with chromic acid.

Lucas reagent

Is a solution of zinc chloride in concentrated HCl.

True

Tertiary alcohols react immediately.

5 to 10 minutes

How many minutes will secondary alcohols become cloudy.

no reaction

Primary alcohols give (reaction / no reaction) in a reasonable length of time.

blu-violet

Phenols form highly colored coordination complexes with ferric ion. A ________ colored solution results.