Reactions stopping

[prepare]

� Equation 1 - 2CuCO3(s) Cu2O(s) + 2CO2(g) + �O2(g)

� Equation 2 - CuCO3(s) CuO(s) + CO2(g)

Does anyone know how i would know when the above 2 reactions have finished (stopped reacting). The best i can think of is that gas will stopped being produced and i think Cu2O(s) is red. Is there any other ways of doing this such as measuring pH and possible technique. Any suggestions welcome including further ellaboration on the above two.

[Hamish]

It would depend on how you are decomposing/reacting CuCO3. I would go for measuring the volume of gas (1) and mass of residue (2). There are many other things you could do it would depend on how accuraely you want to do the measurement, how much materials you are working with and how you are doing the decomposition. I guess this is home work and if this is the whole question I would suggest you are thinking along the right lines.

[xyave]

i have to do a plan of this very same experiment to measure the volume of gas produced and how i did it, can you please tell me how you set up the experiment, was your gas collected in a gas collector or in a measuring cylinder under water? any help at all would be very much apreciated as i am having trouble getting myself organised and where to start planning the experiment. thanks

[prepare]

thanks hamish all i need is theoretical ways of knowing when the reaction has stopped no matter how complicated as long as its A level material i think

my method is to heat copper carbonate collecting gas in a gas syringe and NOT a measuring cylinder underwater.