Question

Question #4670c

Answer 1

Atomic number for magnesium is `12`. The nucleus contains `12"p"^+ and 12 "n"^@`

As per Bohr's model the electrons could be arranged inside the atom as per following

• Each shell or energy level can contain only a fixed number of electrons.
• The general formula proposed by Bohr was that the `n^(th)` shell can contain up to `2(n^2)` electrons. Where `n=1,2,3....` and is the shell number.
• The first shell can hold up to two electrons
• The second shell can hold up to eight electrons
• The third shell can hold up to eighteen electrons and so on.

Therefore,

First `2` electrons will fill in the `"First shell " n=1`,
Next `8` electrons will fill in the `"Second Shell "n=2`,
Remaining `2` electrons will go in the `"third shell "n=3`.