What is the chemical equation for titration of #HCl + NH_3#?

1 Answer
Jul 31, 2016

Answer:

#"NH"_ (3(aq)) + "HCl"_ ((aq)) -> "NH"_ 4"Cl"_ ((aq))#

Explanation:

Hydrochloric acid, #"HCl"#, a strong acid, will react with ammonia, #"NH"_3#, a weak base, to form aqueous ammonium chloride, #"NH"_4"Cl"#, according to the following chemical equation

#"NH"_ (3(aq)) + "HCl"_ ((aq)) -> "NH"_ 4"Cl"_ ((aq))#

In this particular reaction, the chloride anions, #"Cl"^(-)#, act as spectator ions, which means that you can eliminate them from the balanced chemical equation to get the 8net ionic equation*

#"NH"_ (3(aq)) + "H"_ ((aq))^(+) -> "NH"_ (4(aq))^(+)#

It's worth mentioning that because you're titrating a strong acid with a weak base, the pH of the resulting solution will be lower than #7# at equivalence point.

That is the case because this neutralization reaction produces the ammonium cation, #"NH"_4^(+)#, which acts as a weak acid in aqueous solution.

Assuming that you're running ammonia into hydrochloric acid, the titration curve will look like this

http://www.chemguide.co.uk/physical/acidbaseeqia/phcurves.html