Question

sugar and salt are solids, but when they are mixed thoroughly into water, the solids can no longer be seen. which statement explains what happens when these three substances are mixed?
a. the water reacts with the salt and sugar to form a new substance.
b. the water causes the salt and sugar to dissolve and form a solution.
c. the salt and sugar combine with the water and form a solid substance.
d. the salt and sugar evaporate into the air when they are mixed with the water.

Explanation:

• Option A: Mixing salt and sugar with water is a physical process (dissolving), not a chemical reaction to form a new substance. So A is incorrect.
• Option B: Water is a solvent that dissolves solutes (salt and sugar) to form a homogeneous solution, where the solutes are dispersed at the molecular level and no longer visible as solids. This matches the observation.
• Option C: Salt and sugar dissolve in water, they don't combine with water to form a new solid substance. So C is incorrect.
• Option D: Salt and sugar dissolve in water (they don't evaporate into the air in this context; evaporation of water would later allow them to be recovered, but during mixing, they dissolve). So D is incorrect.

Answer:

B. The water causes the salt and sugar to dissolve and form a solution.