A few days ago

Synthesis/analysis of alum?

I was doing a lab in AP Chem over the synthesis/analysis of alum, but I have these questions that I need help with.

How does the solubility of alum in water change with the temperature?

Why should you NOT wash the crystals with water?

Top 2 Answers
A few days ago
Shirley Q

Favorite Answer

Solubility of alum in water increases as temperature increases. When you heated the alum and water together no alum crystals were seen. Later, when the solution cools off, the crystals appear because of the lowered solubility of alum in lower temperatured water.

Water will dissolve the alum that you worked so hard on getting. Using ethanol to rise the crystals will not dissolve the crystals.


4 years ago
Analysis Of Alum