Condensed structural formula of propane is:
(A) $CH_{ 3 }-CH_{ 2 }-CH_{ 3 }$
(B) $CH_{ 2 }-CH_{ 3 }-CH_{ 3 }$
(C) $CH_{ 2 }-CH_{ 4 }-CH_{ 2 }$
(D) None of the above

Question

Condensed structural formula of propane is:(A) $CH_{ 3 }-CH_{ 2 }-CH_{ 3 }$(B) $CH_{ 2 }-CH_{ 3 }-CH_{ 3 }$(C) $CH_{ 2 }-CH_{ 4 }-CH_{ 2 }$(D) None of the above

Vedantu Content Team · Accepted Answer

Hint: A condensed structural formula is a system of writing structures in a line of text. Now you can see which condensed structural formula is correct for propane.

Complete step by step answer:
- Propane is also called n-Propane. It is a gas molecular entity and acts as a food propellant.
- Condensed structural formula - A condensed structural formula is a system of writing organic structures in a line of text. It shows all atoms, but omits the vertical bonds and most or all the horizontal single bonds.
- In propane, prop means three carbons and ane means alkane. So, it is an alkane having three carbon.
- Standard formula for alkane is $C_{ n }H_{ 2n+2 }$. Where n is the number of carbon atoms.Hence, Molecular formula for propane is $C_{ 3 }H_{ 8 }$.
- A carbon atom can have only 4 valencies, that means it can be attached with another 4 atoms.
- In all first three options, the way of writing condensed structural formula is correct if we don't consider the valency of carbon atoms.
Only option (A) , $CH_{ 3 }-CH_{ 2 }-CH_{ 3 }$ satisfies all the valencies of carbon atoms.
Therefore, the correct option is A.

Additional information: Propane was discovered in the year 1857 by Marcellin Berthelot who was a French chemist.
1) n-Propane is a colourless gas which has a faint petroleum-like odour.
2) It is soluble in ethyl ether, chloroform, water, and benzene.
3) It is usually obtained as a by-product of two other processes viz petroleum refining and natural gas processing. It is widely used as a fuel.

Note: We should know that a condensed structural formula is also known as a semi-structural formula. In a condensed structural formula covalent bonds are not always shown and atoms of the same type bonded to one another are grouped together.
When the formula is written in a line with covalent bonds shown, it is also referred to as a linear formula.