Amphoteric Compounds

[Nicole Jakiel 4F]

Can anyone clarify how do we identify amphoteric compounds? For example, is there any specific way to tell by looking at the compound's structure?

[WilliamNguyen_4L]

I think we just have to memorize which ones on the periodic table would be amphoteric. I guess another way to see is if in the reaction, if you know that one reactant is definitely always a acid or base, the other reactant would be amphoteric.

[Jocelyne Milke 1G]

Some of them include BeO, Al2O3, Ga2O3, SnO2 & PbO2. They have characteristics in between metal oxides and nonmetal oxides

[Dong Hyun Lee 4E]

I understand that amphoteric compounds can act as both bases and acids but how do we figure out when it acts as which. Is it that one part of the chemical equation will be an aid so the amphoteric compound would result in a base or how would this work?

[WilliamNguyen_4L]

If the amphoteric compound is reacting with an acid it's a base. If it's reacting with a base it's an acid.

[Alan Chang]

Some amphoteric compounds you can also deduce. For example, seeing water, you can deduce that it can lose its H+ ion (proton) to form OH- (acting as Bronsted acid) and you can deduce that it can accept a H+ ion (proton) to form H3O+ (acting as Bronsted base) therefore deducing that it is amphoteric.