Iodine solution tests for starch
Benedict's reagent tests for reducing sugars or aldehydes
The Iodoform reaction tests for the presence of methyl ketones, or compounds which can be oxidized to methyl ketones
The Schiff test detects aldehydes
Tollens' reagent (Silver Mirror) tests for aldehydes
Lucas' reagent is used to determine mainly between primary, secondary and tertiary alcohols.
Flame tests test for metals