How can you tell if a compound is a Bronsted-Lowry acid or base?

Question

I know the definition but how do you determine if something will give up a proton or take in a proton in solution with water?

Answer 1

You really have to learn each case. NH4+ is a Bronsted acid, but CH4 is not. Also, Bronsted-Lowry theory does not depend on water. That's how they get beyond the Arrhenius theory, which requires H3O+ and OH- in water.

NH3(g) + HCl(g) ===> NH4Cl(g)

is a Bronsted neutralization.

Answer 2

proton skill H+, so hi dissociates inti H+ & I- i.e it donates proton steadily. while CH3COO-, H2PO4-, HSO4- are the conjugate bases of the acids CH3COOH, H3PO4, H2SO4 respectively. as a consequence, conjugate base + H+ = acid i.e it accepts proton