JEE Main 2026 · 5 Apr · Shift 2 · Chemistry Q64

ChemistrySingle correct+4 / -1Question 64 of 75

Identify the correct IUPAC name of hydrocarbon ( $x$ ) containing three primary carbon atoms and with molar mass 72 g mol $^{-1}$ .

1, 1 - Dimethylcyclopropane

2, 2 - Dimethylpropane

2 - Methylbutane

n-pentane

Answer and worked solution

Official answer: C

Formula. Molar mass 72 g mol $^{-1}$ fits $\ce{C5H12}$ , a pentane. 1,1-Dimethylcyclopropane is $\ce{C5H10}$ (70), so it is out.

Primary carbons in each pentane:

Answer: 2-methylbutane.

(C)

Topics:IUPAC nomenclature Alkanes

JEE Main 2026 · 5 Apr · Shift 2, Chemistry question 64