aldehydes and ketones

What can a primary alcohol form when oxidized?

It can be distilled and form An aldehyde

Or a carboxylic acid

What can a secondary alcohol form when oxidized?

A ketone

What can a tertiary alcohol form when oxidized?

Not

What oxidizing agents can be used to oxidize alcohols?

Acidified dichromate

Potassium permanganate

What test can you use to determine if a solution contains an aldehyde or ketone?

Tollens Silver mirror test or Fehlings

Positive test for Fehlings

Brick red precipitate, aldehyde is present

What is the Positive result for Tollens reagent (Silver mirror test)

Silver mirror forms or black precipitate (silver oxide) forms

Aldehyde is present

Why must you rinse out the test tube immediately after doing the Tollens reagent test?

Because the product can explode

Compare the nucleophilic addition in aldehydes and ketones

Addition of the C=O bond

They are attacked by nucleophiles at the positive carbon centre

What reagents can be used in nucleophilic addition of carbonyl compounds?

KCN(aq) or NaCN

To form the -CN nucleophile

Draw the mechanism for the nucleophilic addition of propanal

What are Allene’s attacked by in nucleophilic addition?

Electrophiles

Draw and explain the structure of a Carbonyl group

Polar bonds due to the difference in electronegativity between the carbon and oxygen atom.

Planar shape

Explain how in nucleophilic addition to compind with carbonyl groups can result in optical isomers

Due the carbonyl group having a planar shape

Nucleophilic attack can happen on the top or bottom

Resulting in 2 optical isomers that can form

Describe the structure of an Aldehyde

One H attached to Carbonyl group

Describe the structure of a Ketone

2 carbon atoms attached to carbonyl group

State the structural formula of C3H6O and the displayed formulas it can have and state the functional groups

Explain why when comparing different carbonyl compounds that the comparisons of their MR should be relative?

The bigger the size of the compunds

The stronger the van dear waals forces

So the intermolecular forces are greater and more energy is needed to overcome them

Which is more soluble? An alkane, alcohol or ketone?

If it’s water it is alcohol due to it having a high boiling point, it can hydrogen bonding, and the OH bond is polar

If it is organic solvent it is Alkane because the solvent is non-polar and Alkanes are non-polar