Frequently Asked Question

To test for alkanols, you can perform the following steps:

1. Lucas Test: Add the suspected alkanol to anhydrous zinc chloride (Lucas reagent). Observe the reaction.
- For primary alkanols, there will be no reaction or a slow formation of an upper layer.
- For secondary alkanols, there will be a slow formation of a cloudy layer.
- For tertiary alkanols, there will be an immediate formation of a cloudy layer.

2. Chromic Acid Test: Add the suspected alkanol to a solution of potassium dichromate in sulfuric acid (chromic acid). Observe the color change.
- Primary alkanols will oxidize to form aldehydes, which will further oxidize to carboxylic acids, resulting in a color change from orange to green.
- Secondary alkanols will oxidize to form ketones, which will not further oxidize, resulting in a color change from orange to green or brown.
- Tertiary alkanols do not react with chromic acid and no color change is observed.

3. Esterification Test: React the suspected alkanol with an acid anhydride or acid chloride in the presence of a catalyst (usually sulfuric acid). Observe the formation of an ester product.
- Alkanols will react with acid anhydrides or acid chlorides to form esters. This reaction can be confirmed by the characteristic fruity odor of the ester product.

4. Acetylation Test: React the suspected alkanol with acetic anhydride in the presence of a catalyst (usually pyridine). Observe the formation of an acetyl derivative product.
- Alkanols will react with acetic anhydride to form acetyl derivatives. This reaction can be confirmed by the characteristic odor of the acetyl derivative product or by the formation of a solid precipitate (if the acetyl derivative is insoluble in water).