Question

There are 13 electrons in the third principal level of this atom. Which of the following could it be? a)Mn2+ b)Cl1− c)Ni2+ d)V e)Ge f)Co2−

Answer 1

The atom with 13 electrons in the third principal level from the given options is Co2-.

Step-by-step explanation:

When determining the number of electrons in a particular energy level, you need to know the principal quantum number (n) and the maximum number of electrons that can occupy that energy level. The formula for calculating the maximum number of electrons is 2n^2. For the third energy level (n=3), the maximum number of electrons is 2x3^2 = 18.

Since there are only 13 electrons in the third principal level of this atom, it indicates that the atom is not fully occupying the third level. The only element from the given options that has 13 electrons in the third energy level is Co2-.