........ Chemical Equation for this Titration .......?

Question

What is the chemical equation for this experiment?

The experiment is to find the amount of Nitrogen in fertiliser.

Firstly you dissolve 10g of the fertiliser into some distilled water, add sodium hydroxide and then titrate the solution with hydrochloric acid [all chemicals are of known concentrations]. And then note how much HCl was used.

So, the things that are important are:
Sodium Hydroxide [NaOH],
Hydrochloric Acid [HCl], and
the fertiliser

I’ve done the whole experiment I just need the chemical equation. I would really appreciate any help with this, thanks.

ps- the equation wasn't with the experiment

Answer 1

It was an ammonium fertiliser.

(NH4)+ + OH- ----> NH3 + H2O

So all the ammonium was converted into ammonia.

You then titrated the ammonia with HCl:

HCl + NH3 ----> NH4Cl.

As far as I can see, though, the design of this experiment is deeply flawed, and all that you are going to get out of it is a measure of how much NaOH you put in - unless you boiled the solution to get rid of the ammonia, and then titrated the excess NaOH. That would work:

HCl + NaOH -----> NaCl + H2O