An atom of an elemets has three elctons in the third shell which is the outermost sell .Write
(a) the electronic configureation , (b) the atomic number
(c ) Eclectronic configuration : 2,8,3 , (d) Valency
(e ) the name o f the element , (f) its nature whether metal or non metal

Explanation

The third shell is M shell .If the atom of the element has three electons in the third this means that K and L shells are already filled
(a) Electronic configuration : 2,3,8 , (b) Atomic number =No of electrons =13
(c ) Number of protons =No of electrons -=13 , (d) Valency of the element =3
(e ) The element with Z=13 is aluminium (Al) , (f) It is a metal