Which of the following correctly describes the carbon–magnesium bond and the magnesium–halogen bond in a Grignard reagent, RMgX?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → C–Mg bond: covalent but highly polar; Mg–X bond: essentially ionic
A Grignard reagent, RMgX, is an alkyl magnesium halide made from a haloalkane and magnesium in dry ether.
Magnesium is electropositive, so the carbon pulls the shared electrons of the C–Mg bond towards itself: the bond is covalent but highly polar, with carbon carrying the negative end.
The Mg–X bond, between the metal and a halogen, is essentially ionic.
NCERT (2026-27 edition):
6.7.1 Reactions of Haloalkanes – “In the Grignard reagent, the carbon-magnesium bond is covalent but highly polar, with carbon pulling electrons from electropositive magnesium; the magnesium halogen bond is essentially ionic.”