Q12.What are the hydrocorbons write the name and general formula of (i) saturated
hydrocarbons, (ii) unsaturated hydrocarbons, and draw the structure of one hydrocarbon of
each type.
Answers
Answer:
Hydrocarbons are organic compounds composed of elements of carbon and hydrogen only. The molecular formula for hydrocarbon compounds is CxHy. There are different types of hydrocarbons such as saturated hydrocarbons, unsaturated hydrocarbons, cycloalkanes, aromatic hydrocarbons and aliphatic hydrocarbons.
(a) Saturated hydrocarbons
These are simplest hydrocarbons in which carbon-carbon atoms and carbon-hydrogen atoms are held together by single bonds. They have Sp3 hybridised carbon atom and called as alkanes having a general formula CnH2n+2.
Example:
Ethane (C2H6) can also be written as CH3 – CH3.
(b) Unsaturated hydrocarbons
These compounds consist of a single, double or a triple bond between carbon-carbon atoms. The double-bonded compounds are called alkenes and the triple bonded compounds are called alkynes. The general formula for alkenes is CnH2nand for alkynes the general formula is CnH2n-2.
Example:
Alkene – Ethene:- CH2 = CH2
Alkyne – Ethyne:- CH ≡ CH
Explanation:
ANSWER
1. Hydrocarbons are organic compounds that are made of only hydrogen and carbon atoms.
2. Saturated hydrocarbons have only single bonds between carbon and hydrogen atoms and are called alkanes.
General formula: C
n
H
2n+2
Ethane:- CH
3
−CH
3
3. Unsaturated hydrocarbons have double and triple bonds between carbon atoms. They are alkenes and alkynes.
General formula: alkenes: C
n
H
2n
and alkynes: C
n
H
2n−2
Ethene (Alkene):- CH
2
=CH
2
Ethyne (Alkyne):- CH≡CH
4. Unsaturated hydrocarbons can be converted to saturated hydrocarbons by addition of hydrogen which breaks the double or triple bond.
CH
2
=CH
2
+H
2
→
Ni
CH
3
−CH
3