copper oxide decomposing

[prepare]

When copper dioxide decompes either of the following will happen:

2CuCO3(s) --------- Cu2O(s) + 2CO2(g) + �O2(g)

or

CuCO3(s) --------- CuO(s) + CO2(g)

for my A - level chemity coursework could someone tellme asap (please) that if both reactions could happen simutaneously or like i expect only ONE of the above reactions will happen at any one given time

Thank you in advance

[Piper-AK]

They form an equilibrium, so both happen with some molecules of Cu2O decomposing, and some forming constantly. The equilibrium can shift so that the ratio of dioxide changes, but they will still be inter-changing.

[gen2]

Under normal atmospheric conditions with available oxygen, the predominant reaction will be the second one forming cupric oxide. If you include something to 'mop up' the oxygen molecules as soon as they are formed, you should accumulate more cuprous oxide or even reduce it further to metallic copper such as when copper carbonate is heated with carbon.

[prepare]

i meant when carbon carbonate decomposes, sorry

[gen2]

or perhaps even copper carbonate !

[prepare]

lol ye copper carbonate is wot i meant

[Gef]

When copper(II) carbonate decomposes the only products are copper(II) oxide and carbon dioxide. Any A level student should know that.

[prepare]

ye i kno thati was just makin sure thats all that happens. So now i know that does ANYBODY KNOW WHY THE 2nd EQUATION IS CORRECT and the 1st ONE IS WRONG. i think it is because the first equation needs extreme conditions but am not sure????

[Gef]

The first equation is wrong because that reaction NEVER takes place.

[prepare]

well ok, but we were told its very rare but possible under extreme conditions

[Infernal]

dont u have to work out the moles of this equation to prove it????