Research on the Carbonated Drinks as a Teaching Material

Abstract

1. A collecting apparatus of the carbon dioxide in the carbonated drinks on the market such as Cola, Fanta, aerated water and other soft drinks, was devised. Using this apparatus, the carbon dioxide is collected more than 2.5 times by volume of the carbonated drinks. 2. Several pH-indicators reacted on these carbonated drinks. Immediately after the bottle (or can) was opend, the pH of aerated water was measured 4.5, and the value was going on for 6.5 as time passes. The pH of the other soft drinks was between from 2.3 to 2.6, and these values were constant independently of time passing, because these soft drinks resolve a small tartaric acid. 3. The color change of litmus with pH is uncertain, because of a litmus dye is a mixture. Therefore, it is unsuitable to use the litmus solution to carbonic acid, even if the concentration of carbonic acid is the maximum at ordinary temperature, the litmus solution will not change color so clearly, and the litmus paper too.