Question

Label each reactant and product in this reaction as a bronsted acid of base

H2Y- + H2Z- >< H3Y + HZ2-

Answer 1

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)

Note that, typically conjugate bases/acids are shown in the right (product) side

So, from your reaction:

H2Y- transforms to H3Y; it is gaining and H+, so it is a BASE

H2Z- transforms to HZ2-; it is losing H+, so it is an ACID

then,

H3Y is the conjugate ACID (since it could donate H+ to form H2Y-)

and HZ2- is the conjugate BASE ( since it could accept H+ to form H2Z-)