Evidence for the existence of neutrons did not come until many years after the discoveries of the electron and the proton. Give a possible explanation.

As there was no electric charge on neutrons, and they did not get affected by electromagnetic fields.

Explanation:

The functions of the neutron in atoms is:

To hold the nuclei with coulombic repulsion between the protons.

The neutron has no charge on it and hence were not discovered.

Its mass is slightly less than the proton.

It provides stability to the atom.

Lord Chadwick is credited to prove the existence and discovery of neutron.

He proved that the nucleus of the atom has its mass in the centre as neutron+ proton.

He bombarded beryllium with alpha particles, and found high energy radiation.

nacl is added to the aqueous of what? ? in order to get a proper answer you have to specify the exact composition of the aqueous solution.