Question

Question 13.3 For the following compounds, write structural formulas and IUPAC names for all possible isomers having the number of double or triple bond as indicated:

(a) C4H8 (one double bond)

(b) C5H8 (one triple bond)

Class XI Hydrocarbons Page 396

Answer 1

concept :- As you know , isomer have same molecular formula but different structure. so, we have to draw all the possible structures of the given compounds and write their IUPAC name .

(a) C4H8 ( one double bond )
isomers of C4H8 have one double bond.
(i) CH3CH2--CH=CH2 (But-1-ene)
(ii) CH3HC=CCH3H ( Cis-but-2-ene)
(iii) CH3HC=CHCH3 ( trans-but-2-ene)
(iv) CH3-C(CH3)=CH2 (2-methylprop-1-ene)


(b) C5H8 ( one triple bond)
isomers of C5H8 having one triple bond.
(i) CH3CH2CH2CΞCH (pent-1-yne)
(ii) CH3CH2--CΞC-CH3 (pent-2-yne)
(iii) CH3--CH(CH3)--CΞCH ( 3-methylbut-1-yne)