# I need Helps . Decomposition Reaction WE

1. Jul 19, 2005

### honeyDew

I need Helps..... Decomposition Reaction WE

is this how you're supposed to write a decomposition reaction in a word equation?

Copper (II) hydroxide decomposes with heat into the copper (II) oxide and water

....so then the water in this one would be a liquid right?

2. Jul 19, 2005

### The Bob

Assuming it is under the correct temperature, the water will be water vapour, thus, a gas.

3. Jul 19, 2005

### honeyDew

well we placed it into a hot water bath ....and constantly stirring it ... the color change so i guess it's gas ...right?

4. Jul 20, 2005

### The Bob

What changed colour? The water?

5. Jul 20, 2005

### Nerro

The colour change tells you that the $$Cu(OH)_2$$ has changed somehow chemically. Since the most likely change is dehydration that is what you should reasonably assume is what happened. Basically the $$Cu(OH)_2$$ was probably hydrated to some extent and what happened is that you have removed this crystal water by heating the hydrate. $$Cu(OH)_2.nH2O(s) \xrightarrow{heat} Cu(OH)_2(s)~+~nH_2O(g)$$ describes this reaction.

When the $$Cu(OH)_2$$ decomposes it leaves $$CuO$$ and $$H_2O$$. The $$H_2O$$ will be released at temperatures of around $$185^{o}C$$ which is unlikely to be achieved in a hot water bath.

6. Jul 26, 2005

### honeyDew

oh I see now...thank you so much for your helps :)