How do I identify if a molecule is a Bronsted Acid or Base?

[JasonNovik3A]

Some examples H2CO3 or NH3 ... how do I figure out of these are Acids or Bases?

[Taylor 1F]

The acid of a compound in Bronsted's definition:is the proton giver. While the base of the compound the proton acceptor. But most compounds are consistent so you just have to know that carbonic acid is an acid and like NH3 is usually a base.

[Bansi Amin 1D]

In the balanced equation, check if the amount of hydrogens increased or decreased. If there was a decrease, that means that the molecule donated the protons (in the form of the hydrogen) and is then a Brønsted acid and if the amount of the hydrogens increased then the molecule accepted the protons and is a Brønsted base.

[Tanaisha Italia 1B]

Another way to think of it is that the N atom in NH3 has a lone pair of electrons so it is an electron donor, which makes it a Lewis base. This also means that it is a proton acceptor and a Bronsted base. H2CO3 is the formula for carbonic acid, so that would be a Bronsted acid.

[404995677]

whats the difference between a Lewis acid/base and a Bronsted acid/ base?

[JonathanLam1G]

whats the difference between a Lewis acid/base and a Bronsted acid/ base?

Lewis acids/bases involve donating/accepting an electron, while Bronsted acids/bases involve donating/accepting H+ ions a.k.a. protons.