The acid-base reaction between HCl and NaOH produces a solution with a pH of 7 at the equivalence point (NaCl H2O). Why does an acid-base indicator that changes color at pH 5 or 9 work just as well for this reaction as one that changes color at pH 7

Answer is in the explanation.

Explanation:

Before the equivalence point, the pH of the solution of HCl that is titrated with NaOH has a pH <<< 7. When you are adding more NaOH nearing, thus, to the equivalence point the change in pH occurs quickly, and, with 1 drop of excess of NaOH after equivalence, the pH of the solution change to a pH >>> 7

That means the volume added at pH 5 or pH 9 is, almost, the same doing the indicator work just as well as an indicator with change color at pH 7

intermolecular forces are the forces between molecules or particles.

there are two kinds of van der waals forces: weak london dispersion forces and stronger dipole-dipole forces.

in molecule of water there are dipole-dipole forces between negatively charged oxygen from one molecule of water and positively charger hydrogen of another molecule of water.

hydrogen bond is an electrostatic attraction between two polar groups that occurs when a hydrogen atom (h), covalently bound to a highly electronegative atom such as flourine (f), oxygen (o) and nitrogen (n) atoms.