Answer:
Option B. Only one of the compounds is an alkane
Step-by-step explanation:
To know which option is wrong us, we simply determine the class to which each diagram belongs.
Diagram 1:
CH4 is called methane and it is a member of the alkane series which are saturated hydrocarbon.
Diagram 2:
CH3CH3 is called ethane and it is a member of the alkane series which are saturated hydrocarbon.
Diameter 3:
CH2=CH2 is called ethene and it is a member alkene series which are unsaturated hydrocarbon.
Diagram 4:
CH3CH2OH is called ethanol which is a member of the alcohol family. CH3CH2OH is also a saturated alcohol as it only contains single bonds.
From the above, we can see that:
1. Only one compound is alcohol i.e CH3CH2OH.
2. There are two members of the alkane series i.e CH4 and CH3CH3.
3. Only one compound is unsaturated i.e CH2=CH2. Unsaturated compound has one or more double bond.
4. Only three compounds are hydrocarbon i.e CH4, CH3CH3 and CH2=CH2. Hydrocarbons are compounds containg only carbon and hydrogen.
Therefore, option B is wrong as there are two members of the alkane present.