Example from Lecture

[Will Harvey 1B]

I was a little confused on how the reaction HCl+NH3 -> NH4CL results in an acidic solution because I thought that Cl does not contribute to pH at all. Should I be focusing more on the NH3 on this one?

[Nathan Tran 1B]

Yea so the salt that is formed is NH4Cl. The ions of that is NH4+ and Cl-. NH4+ is a conjugate acid and Cl- is a conjugate base. Cl- doesn't contribute to the ph because its considered negligible however NH4+, a conjugate acid, is not negligible and thus makes the solution acidic.