Which one of these substances will exist in solution only as molecules?

A. CH3NH2

B. LiOH

C. NH4OH

D. CH3OH

The substances which will exist in molecular form in solution are-

A. CH₃NH₂

D. CH₃OH

The methyl amine (CH₃NH₂) and methanol (CH₃OH) is organic compounds which are hardly become ionic in nature and prefers to form as molecular state in the solution phase.

On the other hand B. LiOH and C. NH₄OH are inorganic compound and highly ionic in nature and remain as ionic state in solution.

Those are-

LiOH (s) → Li⁺ (s) + OH⁻ (s)

NH₄OH→ NH₄⁺ (s) + OH⁻ (s)