Answer:
The atomic number of the atom is 14.
Explanation:
The following data were obtained from the question:
Valence electrons = 4
Atomic number =.?
From the question given, we were told that the valence electron is in the m shell. Thus, we can say:
M shell = 4 electrons
The number of shells of the atom can be written in the order K, L, M with M as the last shell because we were told that the valence electrons i.e electrons in the outer shell is located at the M shell.
From a detailed knowledge of atom,
K shell = 1st shell
L shell = 2nd shell
M shell = 3rd shell
The first shell, K of an atom can only accommodate 2 electrons while others can accommodate a maximum of 8 electrons.
Note: we can only put electrons in another shell if a shell is already having 8 electrons. This rule only applies to the 2nd shell and above.
Thus, the atom in question has the following electrons:
K shell = 1st shell = 2 electrons
L shell = 2nd shell = 8 electrons
M shell = 3rd shell = 4 electrons
To get the atomic number of the atoms, we simply add all the electrons together.
This is illustrated below:
Atomic number = 2 + 8 + 4
Atomic number = 14
Therefore, the atomic number of the atom is 14.
