If you like us, please share us on social media.
The latest UCD Hyperlibrary newsletter is now complete, check it out.

GeoWiki.png
ChemWiki: The Dynamic Chemistry E-textbook > Development Details > Approaches > Demos > Additional Demos > The Chemistry of the Bicarbonate Ion

The Chemistry of the Bicarbonate Ion

Chemical Concepts Demonstrated

Demonstration

Three balloons are attached to three bottles as shown in the picture.
  • All of the balloons contain Alka-Seltzer.
  • The first bottle contains 250 ml of water.
  • The second bottle contains 250 ml of water and 3 ml of HCl.
  • The third bottle contains 100 ml of water and 150 ml of a soft drink.
bicarb.gif

Drop the alka-seltzer into the bottles.

Observations

The more acidic the solution, the larger the amount of CO2 gas is produced.   These amounts can easily be measured by comparing the resulting size of the balloons.  The plain water produces the least amount of gas, the water and hydrochloric acid produces a moderate amount, and the water and soft drink produce the most gas.

Explanation (including important chemical equations)

HCO3- (aq) + H+ (aq) <=> H2CO3 (aq) <=> H2O (l) + CO2 (g)

HCl is a stronger acid than water.  Larger amounts of acid will increase the acidity of the solution and push the reaction towards the production of products (i.e. more acidity yields more CO2 gas).

Contributors

You must to post a comment.
Last Modified
10:30, 2 Oct 2013

Page Rating

Was this article helpful?

Tags

Creative Commons License UC Davis ChemWiki is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License. Permissions beyond the scope of this license may be available at copyright@ucdavis.edu. Questions and concerns can be directed toward Prof. Delmar Larsen (dlarsen@ucdavis.edu), Founder and Director. Terms of Use

By STEMWiki Hyperlibrary