Answer: The correct answer is Option 2.
Explanation:
Hydrocarbons are defined as the compounds which have a covalent bond present between hydrogen and carbon atoms. For Example: \(CH_4\) is a hydrocarbon. \(H_2O,CO_2\) are not considered as hydrocarbons.
For the given options:
Option 1: butanal
The chemical formula for this compound is \(CH_3CH_2CH_2CHO\)
This is not considered as a hydrocarbon because a covalent bond is present between carbon and oxygen atom.
Option 2: butyne
The chemical formula for this compound is \(CH\equiv CCH_2CH_3\)
This is considered as a hydrocarbon because covalent bonds are present between carbon and hydrogen atoms only.
Option 3: 2-butanol
The chemical formula for this compound is \(CH_3CH(OH)-CH_2CH_3\)
This is not considered as a hydrocarbon because a covalent bond is present between carbon and oxygen atom.
Option 4: 2-butanone
The chemical formula for this compound is \(CH_3C(O)-CH_2CH_3\)
This is not considered as a hydrocarbon because a covalent bond is present between carbon and oxygen atom.
From the above information, the correct answer is Option 2.
