A compound with molecular formula C₅H₁₀ shows chain isomerism with CH₃CH₂CH₂CH=CH₂ and lacks geometrical isomerism. What
CH₃CH₂CH₂CH=CH₂ (pent-1-ene) has no geometrical isomerism. CH₃C(CH₃)=CHCH₃ (2-methylbut-2-ene) is a chain isomer, also lacking geometrical isomerism due to identical substituents.
Ref: NCERT Class 11 Chemistry > Chapter 8: Organic Chemistry - Some Basic Principles and Techniques > Topic: Isomerism - Structural Isomerism - Chain Position Functional Metamerism