Q.1. - Organic Chemistry

Question

Question: Three components of the sex pheromone of the female sand bee (Ophrys sphegodes) are saturated hydrocarbons containing 23, 25, and 27 carbon atoms. How many H atoms does each of these alkanes contain? Interestingly, the early spider orchid emits a similar hydrocarbon mixture to attract male sand bees to pollinate its flowers.

Step-by-Step Solution

Answer

Answer

 

The alkanes with 23, 25, and 27 carbon atoms contain 48, 52, and 56 hydrogen atoms, respectively.

Step 1: Saturated hydrocarbons

Saturated hydrocarbons are generally acyclic. Acyclic hydrocarbons are called alkanes. The general molecular formula of alkanes is ${\mathit{C}}_{\mathbf{n}}{\mathit{H}}_{\mathbf{2}\mathbf{n}\mathbf{+}\mathbf{2}}$ , where n is the number of carbon atoms.

Step 2: Explanation

The given saturated hydrocarbon contains 23, 25, and 27 carbon atoms. 

The number of hydrogen atoms for the given alkanes is calculated as follows:

When the value of n is 23,

 $C_{23}{H}_{2\times 23+2} =C_{23}{H}_{48}$.

When the value of n is 25,

$C_{25}{H}_{2\times 25+2}=C_{25}{H}_{52}$ .

 

When the value of n is 27,

$C_{27}{H}_{2\times 27+2} = C_{27}{H}_{56}$ .

 

Therefore, the alkanes with 3, 25, and 27 carbon atoms contain 48, 52, and 56 hydrogen atoms, respectively.