help on prac question (1 Viewer)

[EViL.GENiUS]

QUESTION

Explain why the mass of carbon dioxide formed increases, and then levels off?

 

[study-freak]

20 grams of CaCO3 neutralised HCl completely.
Hence adding more CaCO3 when m<20grams led to steady production of CO2, but after using up all H3O+ in HCL when m=20grams, no reaction occurs, stopping the production of CO2.
CaCO3(s)+2HCL(aq)->CO2(g)+H2O(l)+CaCl2(aq)

I did it qualitatively but depending on the marks allocated, the Q might want you to calculate the mass of CaCO3 that completely neutralises the HCl used.

 

[undalay]

^ is correct.
In excess of carbonate, HCl becomes the limiting reagant instead of carbonate.