A polar solvent is described as water-soluble and flammable; which of the following is a polar solvent?

A polar solvent is described as water-soluble and flammable; which of the following is a polar solvent?

• A. Ethanol
• B. Acetone
• C. Gasoline
• D. Water

Answer: (B)

A polar solvent has molecules with an uneven distribution of electrical charge, creating a dipole that interacts strongly with water and other polar substances. Acetone does just that: its carbonyl group (C=O) gives it a significant dipole moment, so it mixes readily with water and is water-soluble. At the same time, acetone is highly flammable because of its volatility and low boiling point. That combination—polarity that promotes water solubility and a low flash point that makes it flammable—makes acetone a classic polar solvent. Water is polar but not flammable, gasoline is nonpolar, and while ethanol is polar and flammable and water-soluble, acetone is the example commonly cited for a polar solvent with those properties.

A polar solvent has molecules with an uneven distribution of electrical charge, creating a dipole that interacts strongly with water and other polar substances. Acetone does just that: its carbonyl group (C=O) gives it a significant dipole moment, so it mixes readily with water and is water-soluble. At the same time, acetone is highly flammable because of its volatility and low boiling point. That combination—polarity that promotes water solubility and a low flash point that makes it flammable—makes acetone a classic polar solvent. Water is polar but not flammable, gasoline is nonpolar, and while ethanol is polar and flammable and water-soluble, acetone is the example commonly cited for a polar solvent with those properties.