What color is carbon dioxide

Info 1: Carbonic acid and carbon dioxide

One speaks of in everyday life carbonic acid, so the gas bubbles in the fizzy drink or in the lemonade are usually meant, i.e. the carbon dioxide. So are carbonic acid and carbon dioxide the same? From a chemical point of view there are clear differences!

  • Carbon dioxide is a colorless, odorless gas.
  • If you add carbon dioxide to water, carbonic acid is produced.
  • The carbonic acid makes the water acidic.

As for the last point, carbonic acid is no different from any other acid: It forms acidic solutions with water. That is the reason why “sour sparkling water” is actually sour, just like all other “carbonated” drinks: lemonade, cola, beer, ...

But one thing is quite different with carbon dioxide than with other acids. It can only exist in the presence of water, i.e. pure carbonic acid there is not any! What you see as bubbles in the sparkling water is not carbonic acid, but carbon dioxide. If you try to isolate the carbon dioxide by evaporating the water "around it", then it breaks, it disintegrates.


  • Put about 50 mL of the sour sparkling water in a beaker.
  • Add a few drops of universal indicator solution and determine the pH.
  • Gently heat the beaker so the water evaporates. Watch the color.


The described formation of carbonic acid is a chemical reaction. *

  • Formulate a reaction scheme! *
  • Formulate a reaction equation! Help: carbonic acid has the chemical formula H2CO3 *


Information LernBox Carbon Dioxide Part 1: Download [docx] [182 KB]

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