Question

The number of electrons, protons and neutrons in a species are equal to 10, 12 and 13

respectively. Assign the proper symbol to the species.​

Answer 1

Given info : the number of electrons, protons and neutrons in a species are equal to 10 , 12 and 13 respectively.

To assign : the proper symbol to the species is ...

solution : no of electrons = 10

no of protons = 12

and no of neutrons = 13

we know, atomic number of an element is the number of protons present in one atom of that element.

here atomic no is 12.

electronic configuration of it = 1s² , 2s² , 2p⁶ , 3s²

here you see, period is 3rd and group is 2nd we also see that the outermost electrons are in s subshell so it is an s - block element. this is enough detail to identify the element from periodic table.

it is magnesium.

now no of electrons = 10 < 12

it means magnesium loses its two electrons from its ground state.

i.e., Mg ⇄ Mg²⁺ + 2e⁻

therefore the unknown species is Mg²⁺ in which no of electrons 10 , no of protons 12 and no of neutrons 13.