A list of acids and their sources includes hydrochloric acid, which is produced naturally in the stomach to help the body break down and digest food, and citric acid, which is naturally found in citrus fruits. While hydrochloric acid is considered a strong acid, citric acid is considered weak enough for humans to safely ingest. Industries use citric acid to preserve and pickle foods.
Another acid is sulfuric acid, which is composed of hydrogen, sulfur and oxygen atoms. It is the most commonly found acid and is used in many different industries. For instance, sulfuric acid is used to treat steel and keep it from corroding, as well as make fertilizer. This acid only occurs naturally in minute amounts, produced by decaying organic matter and volcanic activity.
When organic matter decomposes, carbon dioxide forms. In turn, carbon dioxide dissolves naturally in water to produce carbonic acid. Although this process is a natural and important component of the environment, carbonic acid is also used to make carbonated soft drinks.
Tartaric acid can be found naturally in grapes and several plants. This acid is often combined with baking soda to create cream of tartar, a common baking product. It is also used in the production of medication, as a catalyst and in metal cleaning.