CBSE Class 11-science Answered

Following formula is used to calculate the formal charge in any molecule.

 Formal Chrge = (No. of e^- in free atom)-1/2(No. of bonding e-)-(No. of nonbonding e-)

For carbon dioxide first draw the molecule and then calculate for the three atoms.

                                                   O=C=O

For first oxygenatom, FC = (6) -1/2(4)-(4)= 6-6 =0

For carbon atom,  FC = (4) -1/2(8) - (0) = 4-4 =0

For second oxygen atom,  FC = (6) -1/2(4)-(4)= 6-6 =0

 So total formal charge on the molecule is zero.

Bond order is the number of bonding pairs of electrons between two atoms. In a covalent bond between two atoms, a single bond has a bond order of one, a double bond has a bond order of two, a triple bond has a bond order of three, and so on.