Which statement best describes what happens when oil and water are mixed together?

• A. Oil and water do not mix because oil molecules are nonpolar and water molecules are polar, resulting in weak intermolecular forces between them.
• B. Oil dissolves in water due to strong ionic interactions between oil and water molecules.
• C. Oil and water form a homogeneous solution because their intermolecular forces are identical.
• D. Oil and water mix easily because both substances form strong hydrogen bonds with each other.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the nature of the molecules involved. Water molecules are polar, meaning they have a partial positive and partial negative end due to uneven distribution of electrons.
2. Step 2: Recognize that oil molecules are nonpolar, meaning their electrons are distributed more evenly, and they do not have distinct positive or negative poles.
3. Step 3: Recall that polar molecules tend to interact strongly with other polar molecules through dipole-dipole interactions and hydrogen bonding, while nonpolar molecules interact mainly through weaker London dispersion forces.
4. Step 4: Apply the principle "like dissolves like," which means polar substances tend to dissolve in polar solvents, and nonpolar substances tend to dissolve in nonpolar solvents.
5. Step 5: Conclude that because oil is nonpolar and water is polar, they do not mix well; the intermolecular forces between oil and water molecules are weak, causing them to separate rather than form a homogeneous mixture.