Why does oil float on water?

Answer: Oil is less dense than water

Oil is less dense than water ✓ — Correct! Oil molecules are less tightly packed than water molecules, making oil less dense. Less dense substances float on denser ones. Oil also doesn't mix with water because water molecules attract each other more than they attract oil!

Water pushes oil upward — Wrong. Water doesn't actively push oil. Oil floats passively because it's less dense.

Oil repels water molecules — Wrong. While oil and water don't mix, floating is about density, not repulsion.