What is an acid and what is a base? An acid–base reaction is sometimes called a proton-transfer reaction. Explain.

An acid is a substance that donates hydrogen ions (H+) or protons when dissolved in water. In other words, when an acid is dissolved in water, it releases H+ ions. The strength of an acid depends on its ability to donate these protons (and also relies on the concentration of these ions in the solution). A strong acid will readily donate protons and dissociate completely in water, while a weak acid donates less protons and has a lesser degree of dissociation.

A base, on the other hand, is a substance that accepts hydrogen ions (H+) or protons when dissolved in water. Bases can be thought of as proton acceptors. When a base is dissolved in water, it typically dissociates into hydroxide ions (OH-) and a positive ion called a cation. The strength of a base is determined by its ability to accept protons and its concentration in a water solution. Similar to acids, strong bases accept protons readily and dissociate completely in water, while weak bases accept fewer protons and have a lesser degree of dissociation.

An acid-base reaction, also known as a neutralization reaction, occurs when an acid and a base react together, leading to the transfer of one or more protons (H+ ions) from the acid to the base. This transfer of protons results in the formation of a salt and water as products. Because the main event during an acid-base reaction is the transfer of protons from the acid to the base, it is also referred to as a proton-transfer reaction. The acid acts as a proton donor, while the base acts as a proton acceptor. In this way, the substances neutralize each other, with the final result being a balanced solution. The process can be represented by the following general equation: Acid + Base → Salt + Water In summary, acids are proton donors and bases are proton acceptors. An acid-base reaction is sometimes called a proton-transfer reaction because it involves the transfer of protons from the acid to the base, leading to the formation of a salt and water as products.