Lab 25 Date:Red Cabbage Indicator

Purpose

To prepare and test red cabbage as an indicator.

Red cabbage and many other plants contain a water-soluble pigment called anthocyanin.

This pigment changes color when it is mixed with an acid or a base.

Background

Experiment -

Add small pieces of red cabbage to a beaker, add water until it is about half full.

Heat the water to a slow boil for about 10 minutes.

Remove heat,

Add drops of the cabbage indicator to test tubes containing various solutions – see table.

Use a tongs to throw away the leaves and clean up test tubes and beaker

Test Solutions Cabbage Indicator Results

Identify as Acid, Base or Neutral

HCl - Hydrochloric Acid (acid control)

Acid

NaOH - Sodium Hydroxide (base control)

Base

Vinegar solution

Ammonia solution

Ginger Ale

Baking Soda*

* In a test tube, dissolve a small amount of powder in about 30 mL water

Analysis -

Results -