In a titration involving ammonia (NH₃), a weak base, and hydrochloric acid (HCl), a strong acid, the equivalence point occurs when the amount of acid added is stoichiometrically equivalent to the amount of base present in the solution. At the equivalence point, all of the NH₃ has reacted with HCl to form ammonium chloride (NH₄Cl), which is a salt.
At the equivalence point of this titration, the pH will not be neutral (7) due to the nature of the products formed. Instead, the solution will be slightly acidic. This is because the NH₄⁺ ion (the conjugate acid of NH₃) will slightly dissociate in water forming NH₃ and H⁺, leading to a pH below 7.
To determine the pH at the equivalence point more specifically, we would need the concentration of the NH₃ and HCl solutions used in the titration. However, for a typical titration of a weak base (NH₃) with a strong acid (HCl), we can generally expect the pH at the equivalence point to be around 5 to 6.
Conclusion:
While the exact pH at the equivalence point cannot be calculated without additional information such as molarity, it is important to note that it will be less than 7, indicating an acidic solution formed from the salt NH₄Cl.