[semataka]

Hi,
I was solving Chemical Kinetics questions but I stumbled on a question that bothers me even after checking the answer from the answer key. Would you help me with the following question?
Which of the following methods could not be used to determine the rate of the following reaction?

CuCO₃(s) + 2HCl(aq) CuCl₂(aq) + H₂O(l) +CO₂(g)
A measuring the mass of the reaction mixture with time
B measuring the volume of water produced with time
C measuring the pH of the reaction mixture with time
D measuring the volume of gas producecd with time

I was sure that the answer was neither C nor D, so I ruled them out. I knew that volume of the products provided a way to determine the rate of a reaction, so I was left with the option A, which too seemed reasonable. The answer key says the answer is B but does not explain why.

Thank you,
semataka

[chenbeier]

The HCl is dissolved in water and will change to water, the volume will not change.
Compare if you use CuO in this case.

[Borek]

How are you going to measure the volume of water produced?

[semataka]

The HCl is dissolved in water and will change to water, the volume will not change.
Compare if you use CuO in this case.

Oh, for practical reasons, then. Thank you very much.