Question

An atom of helium contains two protons,two electron and two neutrons. Indicate the possible ways of arrangement of these particles in the helium atom?

Answer 1

In theory, there are many possible arrangements. I will describe the possibilities below.

Explanation:

First of all, the nucleus of this atom will contain the two protons and the two neutrons in a very compact bundle. The structure of this nucleus (if indeed there is a definite one) is of no great importance to the chemical nature of the atom.

The two electrons will normally be in what is called the `1s` orbital. This orbital also makes up the entire first electron shell. If the electrons are situated this way, they are at the lowest energy state, which we call the ground state.

Now, if energy is provided to the atom, the electrons can be elevated into any of a large number of higher-energy orbitals, creating what are known as excited states. Since there are very many possibilities for the excited states, it is not possible to list them all.

An atom in an excited state will, in a very short amount of time, return to the ground state by emitting a photon of light.