They both describe any chemical substance that is an acid and a base (like amino acids). Are they interchangeable terms, or is there a specific difference between them?
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Amphiprotic refers to Brønsted-Lowry acids and Lewis acids. It means a substance capable of donating and accepting protons, such as water and bicarbonate. Amphiprotic species must have acidic protons.
Amphoteric refers to Lewis acids. It means a substance capable of acting both as a lone pair acceptor and a lone pair donor, such as aluminium hydroxide and tin dioxide. Amphoteric species don't necessarily need acidic protons.
All amphiprotic substances are amphoteric; not all amphoteric species are amphiprotic.
Amphoteric refers to Lewis acids. It means a substance capable of acting both as a lone pair acceptor and a lone pair donor, such as aluminium hydroxide and tin dioxide. Amphoteric species don't necessarily need acidic protons.
All amphiprotic substances are amphoteric; not all amphoteric species are amphiprotic.
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Amphiprotic means the substance can both donate and accept a proton (H+), while amphoteric is a more general term meaning the substance can act as both an acid and a base. In a sense, water (H2O) can be considered both amphoteric and amphiprotic
H3O+ <------ H2O -----> -OH
here we see that water can potentially do both, gain a proton while acting as a base, and lose a proton while acting as an acid.
So, in a manner, all amphiprotic substances are amphoteric - since when they donate a proton they are acting as an acid, and when they accept a proton they are acting as base.
On the other hand, not all amphoteric substances are amphiprotic, because only in the Bronstead and Lowry sense do acids and bases only accept and donate protons. If you think about Lewis acids and bases - they either accept or donate electron lone pairs, which means that a substance that has more than one mechanism of action could do both a basic and an acidic thing - for example, a metal oxide such as Mg(OH)2, when placed in water can dissociate an -OH ion, which makes it a base, but the Mg can also have water coordinate to it with a lone pair, which makes it a Lewis acid.
H3O+ <------ H2O -----> -OH
here we see that water can potentially do both, gain a proton while acting as a base, and lose a proton while acting as an acid.
So, in a manner, all amphiprotic substances are amphoteric - since when they donate a proton they are acting as an acid, and when they accept a proton they are acting as base.
On the other hand, not all amphoteric substances are amphiprotic, because only in the Bronstead and Lowry sense do acids and bases only accept and donate protons. If you think about Lewis acids and bases - they either accept or donate electron lone pairs, which means that a substance that has more than one mechanism of action could do both a basic and an acidic thing - for example, a metal oxide such as Mg(OH)2, when placed in water can dissociate an -OH ion, which makes it a base, but the Mg can also have water coordinate to it with a lone pair, which makes it a Lewis acid.