Question

What do you mean by polar protic and polar aprotic solvents? What are some examples of these?

Answer 1

Polar protic solvent:

• Polar Protic solvents are polar solvents that have at least 1 hydrogen that is connected directly to a particular electronegative atom such as O-H, N-H, etc., and are capable of forming hydrogen bonds with the solute.
• An important property of protic solvents is that they give Hydrogen gas on reduction which is highly useful in reductive chemistry.
• They are mostly acidic in nature.
• Here S_N1 reactions are faster and S_N2 reactions are comparatively slower.
• Examples of polar protic solvents are water, ethanol, ammonia, HF, acetic acid, etc.

Polar aprotic solvent:

• Polar aprotic solvents are unable to form hydrogen bonds as they do not have any hydrogen atoms bonded with more electronegative atoms like O, N, and F.
• They do not have acidic protons.
• In aprotic solvents, S_N2 reactions are faster whereas S_N1 reactions are comparatively slow.
• Examples of polar aprotic solvents are Acetone, Ethers as well as Chloroform.