Chapter 18, Problem 13STP

To determine

Toexplain: the reason the oxidation numbers of nitrogen and fluorine differ.

Explanation of Solution

Introduction:

The total number of electrons that an atom either receives or loses in order to form a chemical bond with another atom is called oxidation number and it is also known as oxidation state.The oxidation state of noble gas is always 0.

The oxidation number of an element gives information about the charge that a particular element carries. The oxidation number of all the elements in a period differs.

Fluorine and nitrogen both belong to the period of 2 but different groups. Fluorine belongs to group 17 and nitrogen belongs to group 15. The atomic number of nitrogen is 7 and the electronic configuration of nitrogen is 2.5. Thus, it needs 3 electrons to complete its outermost shell and it gains 3 electrons and it will show an oxidation number of 3-.

Similarly, the atomic number of fluorine is 9. Its electronic configuration is 2.7. Thus, it requires one electron to get noble gas configuration, and hence, it gains 1 electron and shows an oxidation number of 1-.

Conclusion:

Hence, the oxidation numbers of fluorine and nitrogen are 1- and 3- respectively as both belong to a different group. On moving left to right, this number decreases and this is why it differs for both the atoms.