Something that can not be undone. Like baking bread..cant be undone.
Answer:
Calcium
Explanation:
"Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.
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According to Bronsted-Lowry reaction- an acid is any substance that donates a proton (H+ ion) to another substance hence these two substance are acid aspirin (acetylsalicyclic acid) and hydrochloric acid (HCl). And there are two pairs - an acid with a corresponding conjugate base and a base with a corresponding conjugate acid. These pairs are called conjugate acid-base pairs.
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