Question

Methene is an alkene with two hydrogen atoms.
(A) True
(B) False

Answer 1

Hint: ‘Meth’ means one carbon atom and ‘ene’ refers to unsaturation by the presence of a double bond. For a double and triple bond to exist any compound should consist of at least two carbon atoms.

Complete step by step answer:
-First we will break the compound name to check for the number of carbon atoms and whether it is saturated or unsaturated.
Methene word is made up of: ‘meth’ + ‘ ene’. ‘Meth’ means the presence of only one carbon atom. The suffix ‘ ene’ refers to the presence of a double bond between 2 carbon atoms.
-We all know that for the presence of a double bond a major requirement is that there should be at least 2 carbon atoms. But this compound name consists of ‘meth’ meaning only one carbon atom.
Hence, as a conclusion alkene cannot exist with just one carbon atom and thus methene does not exist. No such compound can ever be formed.
-The compound can either be methane or ethene.
One carbon atom can form only methane ($C{H_4}$), which has a carbon atom attached to 4 hydrogen atoms via single bonds. Such carbon will have $s{p^3}$ hybridisation and a tetrahedral shape.
While ethene ($C{H_2} = C{H_2}$) is the smallest molecule we can form using one double bond.
-Hence from the above discussion we can conclude that methene does not exist and thus the statement given in the question is invalid.


So, the correct option will be: (B) False


Note: Any hydrocarbon molecule can either be saturated or unsaturated. In saturated hydrocarbons the carbon molecules are attached to each other via single bonds and are known as alkanes. While in unsaturated hydrocarbons the carbon atoms are attached to each other via double or triple bonds. The double bonded compounds are known as alkenes and triple bonded are known as alkynes.