Is NaCl an acidic base or neutral

Neutral salts

Sodium chloride as a neutral salt

Here you can see picture 9 from my presentation "Corresponding acid / base pairs".

methodic procedure

The basic methodological idea that immediately makes sense to any student is this:

An acid gives off protons. In order for a particle to be an acid, it must have hydrogen atoms, which are also bound to another atom with a polar covalent bond.

A base accepts protons. To do this, the particle must have a lone pair of electrons and also have a very high electronegativity.

The two components of the salt are now examined under these two aspects. Is the cation an acid or a base? Is the anion an acid or a base? Then a decision is made as to whether the salt forms a neutral, acidic or alkaline solution with water.

application
  • Is well+ an acid? No, there is no hydrogen atom.
  • Is well+ a base? No, there is no lone pair of electrons.
  • Is Cl- an acid? No, there is no hydrogen atom.
  • Is Cl- a base? Yes, but H2O molecules do not give protons to Cl- from.

The last question is now not that easy to answer for most students. In principle, the chloride ion is a base, albeit a very weak base. That is, the "acid" H2O is unable to donate a proton to a chloride ion. Assuming that such a proton transfer actually occurs, an HCl molecule is formed. The HCl molecule, however, is a strong acid, which immediately returns a proton to an H2O molecule gives off.

So one can summarize that both ions of NaCl are neutral. This explains why a saline solution is neutral, i.e. has a pH value of 7.