What ion makes champagne acidic?

Here's why:

* Fermentation: Champagne undergoes a secondary fermentation in the bottle, which produces carbon dioxide (CO2) and ethanol. This process also releases hydrogen ions (H+) into the wine.

* Acidity: The higher the concentration of H+ ions in a solution, the more acidic it is.

* Tartaric Acid: Champagne also naturally contains tartaric acid, which contributes to its acidity. However, tartaric acid is a weak acid, and its contribution to overall acidity is less than the H+ ions released during fermentation.

So, while the tartaric acid contributes to champagne's acidity, the main reason for its acidity is the hydrogen ions (H+) released during the secondary fermentation process.