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copper sulphate solubility

 

Does anyone know how many grams of copper sulphate ⇦this on eBay or Amazon [affil links] (CuSO4) goes into 100 mL of water, at room temperature to make a "supersaturated" solution?

Tim O'Brien
- Murphy, Texas

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Sure, Tim! We know that! And so do you!

I mean, it's in your CRC Handbook of Chemistry & Physics [adv: on Amazon & AbeBooks & eBay affil links] , which is likely in your high school, college, town, or personal library. 14.3 grams in cold water, 75.4 in hot. What temperature's your room?

Lee Gearhart
metallurgist - E. Aurora, New York

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Hi, Tim.
On webpage ipmwww.ncsu.edu/agchem/chptr10/1007.PDF, I found the solubility of CuS04.5H20 to be 267 pounds per 100 gallons at 32 deg. F.
At www.cdms.net/ldat/mp50R001.pdf, I found it to be 31.6 g/100 cc at 0 °C. You could do the calculation to see if these two sources agree.
At www.uiwtx.edu/~mackinno/alicefiedler/solubility.htm, I saw tables for different temperatures and a graph. It shouldn't take much effort to review these pages and find similar ones so that you can complete your calculation if you understand the principles. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

copper sulphate is soluble in mixture 1:1 of dichlormethane and ethanol?

camelia riscanu
chemist - Romania
February 25, 2009

The values that you get from CRC or other sources (e.g. 32 grams copper sulphate pentahydrate at 20° C) are for a "saturated" solution, you cannot dissolve more for a "supersaturated" solution except by this one trick. Dissolve a larger amount at higher temperature (e.g. 50 g at 60° C), make sure all is dissolved, then cool down. If you are lucky, and have a clean container, the excess will not precipitate out and you will end up with a supersaturated solution.

Daniel Evans
- Los Angeles, California
January 30, 2011