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$NaCl$ with Water and Hexane

APCHEM-IJVJXR

Just because you mix two things together does not necessarily mean that they will form a homogeneous mixture (a solution).

For example, if you add sodium chloride ($NaCl$) to a container that has both hexane and water, the $NaCl$ will dissolve into the water, but will not be found in the hexane $C_6H_{14}$.

Which of the following statements BEST explains these observations?

A

Polar water molecules form ion-dipole forces with the ions of $NaCl$. Hexane, being nonpolar, cannot form these ion-dipole interactions.

B

Nonpolar hexane molecules tend to repel the ions that make up $NaCl$.

C

Nonpolar hexane is less dense that water, so when the two are in the same container, any $NaCl$ that is added to the mixture sinks to the bottom of the container and cannot get into the hexane layer.

D

Nonpolar hexane molecules and water molecules repel one another.