Answer :
Final answer:
In a hot filtration, if crystals appear, you should keep the system as it is and allow the filtration to continue. Adding more solvent or solute, or increasing the temperature, is not recommended.
Explanation:
In a hot filtration, if crystals appear in the filter paper or funnel, it is an indication that the solute is not completely soluble at the lower temperature. To address this, you should keep the system as it is and allow the filtration to continue. By maintaining the current temperature, the solute will continue to dissolve until the solution becomes saturated, and any excess solute will precipitate out as crystals. Adding more solvent (option a) will only dilute the solution and may not increase the solubility of the solute, while increasing the temperature (option b) may cause the solute to dissolve further, but it will also dissolve more impurities. Adding more solute (option c) will increase the amount of the solute that needs to dissolve, prolonging the filtration process.
