How does the color change work with red cabbage juice? Is the red one chemical and the green another?

Also I hear if you add amonia turns it yellowish. There is a trick where you turn "red wine" to "white" by adding amonia...
How does the color change work with red cabbage juice? Is the red one chemical and the green another?
cabbage juice contains a chemical indicator. lots of chemical indicators exist, but they will all change colour based on the pH of the solution (ie how acidic or how basic the solution is). cabbage juice, specifically, turns red when you add it to acid, while it will turn blue/yellow in base. if the solution is neutral, it'll remain purplish. ammonia is a base, thus it will turn it yellow. never heard of red wine tricks...
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