Question

Which of the following can behave as Bronsted-Lowry bases in aqueous solution?

HCO₃^-

Ca(OH)₂

_HCN

_KOH

_{None of the above}

Answer 1

Bronsted Lowery Acid/Bases

First, let us define Bronsted Lowry acid/base:

Bronsted Lowry acid: any species that will donate H+ (protons) in solution, and makes pH lower (i.e HCl)

Bronsted Lowry base: any species that will accept H+ (protons) in solution, and makes pH higher (NH3 will accept H+ to form NH4+)

Typically, acid/bases are shown in the left (reactants)

when we write the products:

Bronsted Lowery conjugate base = the base formed when the B.L. acid donates its H+ proton ( i.e. HCl -> Cl-

Bronsted Lowery conjugate acid = the acid formed when the B.L. base accept its H+ proton ( i.e. NH4+ has accept H+ proton)

HCO₃^- --> this will accept H+, so it is a BL base

Ca(OH)₂ --> will not accept H+, ignore

_HCN --> this is an acid, will donate H+ only

_KOH --> will not accept H+, ignore

From the list only:

HCO₃^- is a Bronsted Lowry base