The blue precipitate dissolves, forming a bright blue (cornflower blue) transparent solution.
This indicates the presence of multiple hydroxyl ( −OHnegative cap O cap H ) groups on adjacent carbon atoms. Step C: Identifying Aldehydes or Glucose
Below is a structured report (essay-style) for this practical work. 1. Define the Objective
Both aldehydes and glucose (which contains an aldehyde group) react with upon heating. Add and heat the mixture gently.
The primary goal of this experiment is to use qualitative chemical reactions to identify unknown organic substances in test tubes, such as . 2. Prepare Reagents and Equipment
Polyhydric alcohols react with copper(II) hydroxide at room temperature. Add freshly prepared to the test tube.
Carboxylic acids can be identified by their acidity or their reaction with carbonates. Add a drop of litmus or a small amount of Na2CO3cap N a sub 2 cap C cap O sub 3 to the sample. Observation: Litmus turns red; Na2CO3cap N a sub 2 cap C cap O sub 3 produces effervescence (bubbles of CO2cap C cap O sub 2 Equation: