In chemistry, an amphoteric substance is one that can react with either an acid or base (more generally, the word describes something made of, or acting like, two components). Chemistry (in Greek: χημεία) is the science of matter and its interactions with energy and itself (see physics, biology). ... An acid (often represented by the generic formula AH) is typically a water-soluble, sour-tasting chemical compound. ... The common (Arrhenius) definition of a base is a chemical compound that either donates hydroxide ions or absorbs hydrogen ions when dissolved in water. ...

Examples include amino acids and water. Many metals, such as zinc, tin, aluminium and beryllium, have amphoteric oxides. For example, zinc oxide ZnO reacts differently depending on the pH of the solution: In chemistry, an amino acid is any molecule that contains both amino and carboxylic acid functional groups. ... A falling water droplet Water (from the Anglo-Saxon and Low German wæter) is a colourless, tasteless, and odourless substance that is essential to all known forms of life and is the most universal solvent. ... General Name, Symbol, Number zinc, Zn, 30 Chemical series transition metals Group, Period, Block 12, 4, d Density, Hardness 7140 kg/m3, 2. ... General Name, Symbol, Number tin, Sn, 50 Chemical series poor metals Group, Period, Block 14 (IVA), 5, p Density, Hardness 7310 kg/m3, 1. ... General Name, Symbol, Number aluminium, Al, 13 Chemical series poor metals Group, Period, Block 13 (IIIA), 3, p Density, Hardness 2700 kg/m3, 2. ... General Name, Symbol, Number Beryllium, Be, 4 Series Alkaline earth metals Group, Period, Block 2 (IIA), 2, s Density, Hardness 1848 kg/m3, 5. ...

In acids:

ZnO + 2H⁺ → Zn²⁺ + H₂O

In bases:

ZnO + H₂O + 2OH^- → [Zn(OH)₄]^2-

This effect can be used to separate different cations, such as zinc from manganese. ... General Name, Symbol, Number manganese, Mn, 25 Chemical series transition metals Group, Period, Block 7 , 4, d Density, Hardness 7470 kg/m3, 6. ...

See also:

• amphiprotic
• ampholytic