The impure acetanilide may not have dissolved in the hot water for several reasons. One reason could be that the impurities present in the acetanilide affected its solubility. Additionally, the temperature might not have been high enough to dissolve the impure acetanilide completely. Another possibility is that the amount of water used was not sufficient to dissolve the impurities.
To get the impure acetanilide to dissolve, there are a few steps you can follow:
1. Increase the temperature: Higher temperatures typically increase the solubility of solids in liquids. Ensure that the water is heated to the maximum temperature possible without causing any hazardous situations.
2. Increase the surface area: Grinding or crushing the impure acetanilide into smaller particles will increase its surface area. This exposes more of the acetanilide to the water, making it easier for it to dissolve.
3. Add more solvent: Increase the amount of water used in the solution. This will provide more medium for the impurities to dissolve into.
4. Stir the solution: Agitating the mixture, either manually or using a stirrer, helps to enhance the contact between the impurities and the solvent, promoting dissolution.
By following these steps, you should be able to increase the chances of dissolving the impure acetanilide in hot water. However, keep in mind that some impurities might be insoluble or may require additional purification techniques.