Question

For SN1 solvolysis of t-butyl chloride, rank the solvents from fastest reaction to slowest reaction?

1) Water
2) Methanol
3) Ethanol
4) Acetone

Answer 1

For the SN1 solvolysis of tertiary-butyl chloride, water is the fastest reaction solvent, followed by methanol, ethanol, and finally acetone, due to the polar protic nature of water, methanol, and ethanol which supports carbocation stabilization. The order of rank is Water, Methanol, Ethanol and Acetone.

Step-by-step explanation:

For the SN1 solvolysis of t-butyl chloride, the reaction rate depends on the ability of the solvent to stabilize the carbocation intermediate and to act as a nucleophile. Polar protic solvents are best suited for this task as they can stabilize ions through hydrogen bonding and solvation. Here's how you would rank the solvents from fastest to slowest reaction:

Water (H₂O)

Methanol (CH₃OH)

Ethanol (C₂H₅OH)

Acetone (CH₃COCH₃)

Water is the most effective solvent for SN1 solvolysis of t-butyl chloride due to its strong hydrogen bonding capabilities and its high dielectric constant, both of which are favorable for stabilizing the carbocation. Methanol and ethanol are also polar protic solvents and would follow water in effectiveness. Acetone, being a polar aprotic solvent, is less effective for an SN1 reaction because it does not participate in hydrogen bonding, which is less supportive of the carbocation intermediate, leading to a slower reaction rate.