Final answer:
Swirling the Erlenmeyer flask during a recrystallization is important to promote even mixing and dissolving.
Step-by-step explanation:
Swirling the Erlenmeyer flask during a recrystallization is important to promote even mixing and dissolving. When a solute is dissolved in a solvent, swirling the flask ensures that fresh solvent molecules continually come into contact with the solute, allowing for faster and more complete dissolution. Without swirling, the solvent near the surface of the solute becomes saturated, making it difficult for additional solute to dissolve.