Acid (noun, “AAH-sid”)
This is any chemical that, when placed in a solution, releases hydrogen ions — atoms with a tiny positive electric charge. The charges make these ions react with bases, which are ions of another type. (Known as hydroxyl ions, those other ions have a negative electric charge.) Acids can eat away at many substances and tend to taste sour. When measured on a pH scale — a zero to 14 ranking of how acidic or basic chemicals are — acids measure below 7.0. And the lower the pH, the stronger — more powerful — the acid.
In a sentence
Acid can help leach dangerous lead out of soils.
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acid A chemical that releases hydrogen ions when dissolved in a solution. Acids have a sour taste and have a pH ranking of less than 7.0.
acidic An adjective for materials that contain acid. These materials often are capable of eating away at some minerals such as carbonate, or preventing their formation in the first place.
base (in chemistry) A chemical that produces hydroxide ions (OH-) in a solution. Basic solutions are also referred to as alkaline. (in genetics) A shortened version of the term nucleobase. These bases are building blocks of DNA and RNA molecules.
hydrogen The lightest element in the universe. As a gas, it is colorless, odorless and highly flammable. It’s an integral part of many fuels, fats and chemicals that make up living tissues.
hydroxyl A chemical group, or pairing. It’s made from an oxygen atom bound to a hydrogen atom, OH. In bases, it is negatively charged.
ion An atom or molecule with an electric charge due to the loss or gain of one or more electrons.
pH A measure of a solution’s acidity. A pH of 7 is perfectly neutral. Acids have a pH lower than 7; the farther from 7, the stronger the acid. Alkaline solutions, called bases, have a pH higher than 7; again, the farther above 7, the stronger the base.