Explain: (i) Dipole moment of chlorobenzene is lower than that of cyclohexylchloride (ii). Alkyl halide though polar, are immiscible with water. (iii). Grignard reagents should be prepared under anhydrous conditions.

Explain: (i) Dipole moment of chlorobenzene is lower than that of cycl

1.	Explain: (i) Dipole moment of chlorobenzene is lower than that of cyclohexylchloride (ii). Alkyl halide though polar, are immiscible with water. (iii). Grignard reagents should be prepared under anhydrous conditions.
Answer» Solution :(i). The polarity of `C-Cl` bond in chlorobenzene is less than that of same bond in cyclohexyl chloride because of carbon atom involved in chlorobenzene is more electronegative (GREATER s-character) as compared to the carbon atom in CASE of cyclohexyl chloride (lesser s-character). therefore, the dipole moment of chlorobenzene is less with respect to cyclohexyl chloride. (ii). In water, `H_(2)O` molecules are linked to each other by intermolecular hydrogen bonding. although alkyl halide also cantain polar `C-X` bonds, they cannot break the hydrogen bonding in `H_(2)O` molecules. this means that there is hardly any scope for association between molecules of alkyl HALIDES and water. they therefore, exist as separate layers and are immiscible with each other. for more details, consult section 6. (iii). Grignard reagents `(R-Mg-X)` should be PREPARED under anhydrous CONDITIONS because these are readily decomposed by water to form alkanes. That is why ether used as solvent in the preparation of grignard reagents is completely anhydrous in nature.