How will the pH water change if you add carbon dioxide?

After blowing into the water, I use litmus paper to measure how the pH change. Will the paper detect any change in pH? will it change color?

I'm afraid that the amount of C02 in my breathe is too low to affect the water pH...

if you blow ambient gas into the water will the litmus paper change color?How will the pH water change if you add carbon dioxide?
When you blow into the water the balanced equation is:

2H2O(l) + CO2(g) ---%26gt; H2O(aq) +H2CO3(aq)

the presence of carbonic acid will lower the pH. Just a note that if you are worried that the CO2 in your breath is too low then use short range pH paper istead of limus you will be able to see the change in pH better.



If you blow ambient gas into the water the pH will not change.How will the pH water change if you add carbon dioxide?
Just stick the litmus paper in club soda (carbonated water). CO2 will change the pH of the water to roughly 5.7. This is only because SOME of the CO2 will react with the H+ atoms to form carbonic acid, lowering the solutions pH slightly. The pH scale represents the amount of H+ in a given substance. Likewise, the pOH scale represents the amount of OH- in a given substance (exact opposite of the pH scale).
It will become acidic (lower pH)

2H2O + CO2 ---%26gt; H3O+ + HCO3-
When you add CO2 to water, you form carbonic acid. The pH will drop.



Litmus paper is a rather crude way to measure pH. You should use a meter, instead.
pH will be lowered as indicated by others. Instead of litmus paper pH papers are available at local fish tank supply stores, swimming pool supply stores or any lab supply store. These could give you a better indication of pH change.



http://cgi.ebay.com/PH-INDICATOR-PAPER-K
CO2 being acidic in nature will change the pH and colour of litmus paper