JEE Main levelSingle correct optionDifficulty 2 of 3pl169
Which statement comparing natural rubber and gutta-percha is correct?
ANatural rubber has cis double bonds and is elastic; gutta-percha is its trans isomer and is hard and non-elastic
BNatural rubber has trans double bonds and gutta-percha has cis double bonds
CBoth have cis double bonds but different molecular formulas
DGutta-percha is more elastic than natural rubber because its chains pack closely
Answer: A
Both are polyisoprenes (CX5HX8)n. The cis chains of natural rubber are kinked, pack poorly and can uncoil on stretching. The trans chains of gutta-percha pack regularly and are stiff.