NH4ClO4 Acidic Salt

[Ronan Ereneta 3D]

Can someone explain why NH4ClO4 is an acidic salt? I don't understand the achieve solution

[Erika Patel 3I]

ClO4- is the conjugate base of a strong acid, and therefore will have a negligible effect on the pH. NH4+ is the conjugate acid of a weak base (making it a stronger conjugate acid) and will therefore cause the solution to be acidic.

[Peter Soliman 1J]

Hi Ronan!

To figure out whether a salt is acidic, basic, or neutral, you have to see to figure out the neutralization reaction.

To do this, I normally split everything up. In the case of this salt, we'll have NH4+ and ClO4-. Additionally, we'll have the water which is created from the acid/base reaction along with the salt:



When we look at the above equation, we'll see that as a result of the acid-base reaction NH4+, ClO4-, H+, and OH- were created. ClO4 has a negative charge, so it will bond with the H+ creating HClO4 (perchloric acid). Perchloric acid is a strong acid. As discussed in class, NH4+ is created through the reaction of NH3 w/ H2O. NH3 is a weak base.

Now, since we know that the salt NH4ClO4 was created using a strong acid and a weak base, we know that the salt is going to be acidic.

Strong Acid + Weak Base = Acidic Salt
Weak Acid + Strong Base = Basic Salt
Strong Acid + Strong Base = Neutral Salt