As the rate of cooling increases, the size of the crystals that form:

• A. decreases
• B. increases
• C. first increases, then decreases
• D. remains unchanged

Answer: (A)

Verified step by step guidance

1. Understand that crystal size during cooling depends on the rate at which the solution or melt cools down from a higher temperature to a lower temperature.
2. Recall that slow cooling allows molecules or ions more time to arrange themselves into a well-ordered, larger crystal lattice, resulting in larger crystals.
3. Recognize that rapid cooling reduces the time available for orderly crystal growth, leading to many small nuclei forming quickly and thus smaller crystals overall.
4. Conclude that as the rate of cooling increases, the size of the crystals formed decreases because faster cooling favors the formation of many small crystals rather than fewer large ones.
5. Therefore, the relationship between cooling rate and crystal size is inversely proportional: faster cooling leads to smaller crystals.