write the conjugate acid for the following:

A.) NO3- =
B.) HPO4^2- =
C.) Br- =
D.) S2- =

Stick a H+ on each.

HPO4^2- + H^+ = H2PO4^-

To determine the conjugate acid for each of the given species, we need to understand the concept of conjugate acids and bases.

Conjugate acids are formed when a base gains a proton (H+) or a hydrogen ion. Therefore, we will add an H+ to the given species to create the conjugate acid. Here are the conjugate acids for each species:

A.) NO3-:
Since NO3- acts as a base, we add an H+ ion to NO3- to create the conjugate acid, which is HNO3 (nitric acid).

B.) HPO4^2-:
In this case, HPO4^2- already contains a hydrogen ion, so we need to add one more H+ ion to create the conjugate acid, which becomes H2PO4- (dihydrogen phosphate).

C.) Br-:
Br- acts as a base, so we add an H+ ion to Br- to create the conjugate acid, which is HBr (hydrobromic acid).

D.) S2-:
S2- acts as a base, so we add an H+ ion to S2- to create the conjugate acid, which becomes H2S (hydrosulfuric acid).

Remember, the conjugate acid is always formed by adding an H+ ion to the base.