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Copper sulphate, equation for decomposition

 

What is the chemical equation for the decomposition of copper sulphate [on eBay or Amazon]pentahydrate?

Sarah Mendlovitz
- Greensboro, North Carolina

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The pentahydrate is 100% isolable only in temperatures lower than 30 °C. The light blue trihydrate non-isolable form can be obtained around 30°C. White monohydrate form is available at 110°C, while the anhydrous form can be isolated near 250°C. The decomposition slightly starts at 250 degrees, while complete decomposition occurs around 600 degrees...

The reaction is as follows: CuSO₄ (aq) ==> SO₂(g) + CuO(s)

Meriçcan Usta
Ted Ankara College - Ted Ankara College, Turkey
 

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2006

Hi, I'm a student at Townsville grammar school in QLD and we're doing a practical on changing copper carbonate to copper (II) sulphate and I was wondering where you got your information about copper (II) sulphate and the degrees it decomposes at;

"At 30°C the light blue tri-hydrate is formed, at 110°C the monohydrate is formed and at 250°C the anhydrous is formed. At 250°C the copper sulphate slightly decomposes however it does not fully decompose till 600°C."

thanks a lot

Courtney J.
student - Townsville, Queensland, Australia

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When copper sulphate is analysed through TGA (Thermogravimetric analysis) it goes as per the literature by losing the water of hydration step by step.

Then, if we continue further, say at around 450 °C there is sudden decrease in weight% of about 13%. So I am doubting whether it is due to decomposition of anhydrous copper sulphate or noise in TGA.

Arunagiri Sachin
- Chennai, Tamilnadu, India
December 6, 2008