Question

Explain the relationship between group number and the number of bonds that ions of elements are likely to form.

Please explain in detial!

Answer 1

During bond formation, when an atom receives electron valancy shell it becomes anion and when an atom loses electron valancy shell it becomes cation. The atoms either lose or gain electron to achieve the nearest noble gas configuration.

During a single bond formation, a unit positive cation and a unit negative anion are united. The group number to an atom is assigned according to the number of valancy electrons present in an atom. Hence the maximum number of bonds that an atom can form is equal to the number of valancy electrons and hence equal to the group number of the atom (maximum upto 8 bonds possible in case of noble gases like Xe ). e.g Alkali metals like Na, K, Rb, Cs, Fr belong to group-1 and having single valancy electron. Hence the maximum number of bonds that they can form is 1.

From group-1 to 7 (1 and2 are S-block elements, 3-7 are d-block elements) the maximum number of bonds formed is equal to group number. For group- 8 to 12, the number of bonds formed is not fixed and is equal to the maximum number of vacancy valancy orbitals they have.

From group- 13 to 18 the maximum bumber of bonds formed are respectively 3, 4, 5, 6, 7 and 8 (in case of noble gas like Xe ).

There is one exception to this rule the p-block elements without having vacancy d-orbital like N, O, F, Ne, the maximum number bonds they can form are respectively 3, 2 and 1.