Will there be any change in the size of common salt crystals if the rate of evaporation is increased or decreased? Explain.
Yes, there will be a change in the size of common salt crystals if the rate of evaporation is altered. The context highlights that salt crystals of different sizes were historically produced using methods with different evaporation rates.
For example, panga salt was obtained by boiling concentrated sea brines, which involves a faster rate of evaporation. In contrast, karkatch salt was produced by the slower evaporation of seawater. Because these distinct processes resulted in different crystal sizes, it is evident that increasing or decreasing the rate of evaporation changes the size of the common salt crystals formed.
Explanation
The textbook context explicitly connects the rate of evaporation to crystal size by citing historical Indian salt-making methods. Boiling (rapid evaporation) produced panga salt, while natural evaporation (slow process) produced karkatch salt, and these methods yielded crystals of different sizes. Therefore, changing the evaporation rate directly impacts crystal size.
Solution Steps
Step 1: Identify from the context that different evaporation methods (boiling vs. natural evaporation) produce salt crystals of different sizes.
Step 2: Conclude that altering the rate of evaporation (increasing or decreasing it) will change the size of the resulting common salt crystals.