Preparation of carbonic acid

Color of litmus solution change when carbon dioxide is bubbled through the solution

Scientific name: Demonstration of acidic properties of carbon dioxide


Получение уголной кислоты

by ФизматФильм

How to make Carbonic Acid (CO2 Method)

Preparation & Properties of Carbonic acid

by Shiva Chemist


Wear lab goggles and gloves. Avoid contact of hydrochloric acid with skin.

Always follow general safety recommendations. Please note that conducting chemistry experiments you must comply with the relevant legal procedures in your country.

Reaction formula

CaCO3 + HCl → CaCl2 + CO2 ↑+ H2O

CO2 + H2O → [H2CO3]

Step-by-step instruction

  1. Pour some water into a beaker.
  2. Add 5-6 drops of litmus.
  3. Put a piece of calcium carbonate (marble) into a test-tube.
  4. Pour hydrochloric acid into the test-tube and close it with a stopper with an outlet tube.
  5. Put the end of the outlet tube into the solution of litmus. The produced gas (carbon dioxide) will bubble through the solution, and the color of the solution will change.

Scientific background

Carbon dioxide CO2 is dissolved in water. When it dissolves in water a partial reaction with forming carbonic acid occurs. It is detected with litmus. The solution changes color from blue to red. Carbon dioxide may be obtained from the reaction of calcium carbonate with hydrochloric acid.


Published on 22 September 2015

  • Fire
  • Heating with fire
  • Explosion
  • Poisoned gas
  • Organic
  • Electricity
  • Solution
  • Oxidation reduction
  • Color change
  • Precipitate
  • Gassing
  • Catalyst