Write the structural formulae of the following compounds :
(a) But-2-en-1-oic acid
(b) 2, 4, 4-Trimethyl-3-isopropylpent-1-ene.

Explanation

(a) But-2-en-1-oic acid
(i) The word root but indicates that the compound has four C atoms.
`C - C - C - C`
(ii) Let us number each carbon atom of the chain as :
`overset(1)C- overset(2) C- overset(3)C- overset(4)C`
(iii) Since its name has 2-en, it means double bond starts from carbon atom no. 2.
`overset(1)C - overset(2)C = overset(3)C - overset(4)C`
(iv) Since the name of the compound ends in 1-oic acid, hence the first carbon atom will have

(v) Attach suitable number of hydrogen atoms.

(b) 2, 4, 4-Trimethyl-3-isopropyl pent-1-ene
(i) As the name of the compound has the word root pent, it has five carbon atoms.
`C - C - C - C - C`
(ii) Let us number each carbon atom of the chain
`overset(1) C - overset(2)C - overset(3) C - overset(4) C -overset(5) C`
(iv) Attach three methyl radicals at 2, 4 and 4 positions and one isopropyl radical at 3 position.

(v) Attach suitable number of hydrogen atoms.