# Question 8132a

Sep 5, 2017

"bond order"=("number of bonding"/" electrons"-"number of non-bonding"/" electrons")/2#

#### Explanation:

And so, for a single bond, say the $C - C$ bond in ethane, we would calculate......

$\frac{2 - 0}{2} = 1$, i.e. a bond order of $1$.

And for a double bond, say the $C = C$ bond in ethylene, we would calculate......

$\frac{4 - 0}{2} = 1$, i.e. a bond order of $2$.

And for a double bond, say the $N \equiv N$ bond in dinitrogen, or the $C \equiv C$ bond in acetylene, we would calculate......

$\frac{6 - 0}{2} = 3$, i.e. a bond order of $3$.

With practice, you will assign these automatically.....

Non-integral bond orders are certainly possible, but these tend not to appear on undergraduate curricula....i.e. $H {e}_{2}^{+}$ and ${H}_{2}^{+}$ are certainly known molecules, not that you could put the stuff in a bottle, and we could give the bond order as.....

$\frac{2 - 1}{2} = \frac{1}{2}$