Question

Why do polar substances dissolve in water?

A. Water molecules break apart polar molecules.
B. Water molecules are attracted to polar molecules and surround them.
C. Water molecules react with polar molecules.
D. Water molecules press on polar molecules, making the molecules very small.

Answer 1

Polar substances dissolve in water because of water's polarity and ability to form hydrogen bonds. Water attracts polar molecules and ions, surrounding them and dissolving them. Non-polar molecules, on the other hand, do not interact with water and separate from it.

Step-by-step explanation:

As a result of water's polarity, each water molecule attracts other water molecules because of the opposite charges between water molecules, forming hydrogen bonds. Water also attracts or is attracted to other polar molecules and ions. A polar substance that interacts readily with or dissolves in water is referred to as hydrophilic (hydro- = "water"; -philic "loving"). In contrast, non-polar molecules such as oils and fats do not interact well with water, as shown in Figure 2.14 and separate from it rather than dissolve in it, as we see in salad dressings containing oil and vinegar (an acidic water solution). These nonpolar compounds are called hydrophobic (hydro- = "water"; -phobic = “fearing").