Among the elements of the 3rd period from Na to Ar, pick out the element: (b). with largest atomic radius.

( a) no. Of electrons in atom of "A " will be only 12 as they are in third period and must have 3 shells and no. Of electrons in...

(a). Ar has highest first ionization enthalpy.

(c). Cl is more reactive non-metal in 3rd period.

(d). Na is most reactive metal in third period. 

Position of P Group-2 Because it has 2 valence electrons/ 2, S, 8, 2 Period-4 Because it has 4 shells/2,8,8,2 Position of Q Croup-17 Because it has 7 valence electrons/ 2, 8, 7 Period-3 Because it has 3 shells/...

It will be 7 in X as well as in Z The reason being that number of electrons in the outermost shell in the elements in same group is same.

Radius of Y is bigger than that of X.   In 'X' the number of shells is three while in Y it is four.

Since the information given in the question is inaccurate, full marks are to be awarded to every candidate.

(i) The position of elements X in the modern periodic table is group number 17 and period number 3. The position of element Y in the modern periodic table is...