Question

Octyne has the same number of hydrogen atoms as that of __________.

• A. heptene
• B. hexene
• C. pentene
• D. butene

Answer 1

The correct option is A heptene

As shown above, octyne has 14 hydrogen atoms.

The above given options are of alkenes and the general formula is ${\text{C}}_{\text{n}}{\text{H}}_{\text{2n}}$.

Since the number of hydrogen atoms in the alkene is 14, using the general formula we get $\Rightarrow 2\text{n}=14$ (where 'n' is the number of carbon atoms).

$\therefore \text{n}=7$

So, the alkene should have 7 carbon atoms and 14 hydrogen atoms.

Comparing the options, butene has 4 carbon atoms, pentene has 5 carbon atoms and hexene has 6 carbon atoms.

The alkene with 14 hydrogen atoms(same as octyne) is heptene.