Question: A student dissolved 0.30 g of a crude product in 10.5mL (the minimum amount required) of ethanol at 25 degrees C. He cooled the solution in an ice-water bath for 15 minutes and obtained beautiful crystals. he filtered the crystals on a Hirsch funnel and rinsed them with about 2.0 mL of ice-cold ethanol. After drying, the weight of the crystals was found to be 0.015 g. Why was the recovery so low?

My answer: The problem is that the solvent dissolves the crude product at room temperature. This makes is highly likely that much of the product remains in solution. It's best to find a solvent that dissolves at boiling point and gives it back at room temperature?

Thanks for checking this.

Sheryl

It looks good to me. I answered a question for Lindz (about half a page down from this post) regarding addition of Br2 and Cl2 to a double bond. Look at them and see if you agree with them. My friend in town will be out of town tomorrow or I would have him look at them. He would know the answers in a flash.