Final answer:
Baking soda and citric acid react in the presence of water to produce carbon dioxide gas, water, and a salt (sodium citrate). Baking soda acts as a Brønsted-Lowry base, accepting protons from the citric acid, which donates protons acting as a Brønsted-Lowry acid. The pH of the solution rises as the acid is neutralized by the base.
Step-by-step explanation:
The interaction of baking soda, citric acid, and water in a chemical reaction produces carbon dioxide gas. When citric acid and baking soda (sodium bicarbonate) come into contact with water, they dissolve and start reacting. Baking soda acts as a base, and citric acid acts as an acid. According to the Brønsted-Lowry theory of acids and bases, an acid is a substance that can donate a proton (H+) and a base is a substance that can accept a proton. The reaction between citric acid and sodium bicarbonate produces sodium citrate, water, and carbon dioxide gas (CO₂).
The pH of the solution will change as the reaction progresses. Initially, the mixture is slightly acidic due to the presence of citric acid. As the reaction occurs, the acid is neutralized by the baking soda, which increases the pH and makes the solution more neutral or slightly basic.