Equal amounts of marble chips are reacted separately with 100cm3 of hydrochloric acid of different concentrations . if all the marble chips reacted, which of the following remained the same in each case?
- Average rate of evolution of gas
-
Total mass of gas evolved during the reaction
- Time taken for the reaction to reach completion
- lnitial reaction rates
The correct answer is: B
Explanation
When marble chips (calcium carbonate) react with hydrochloric acid, they produce carbon dioxide gas, water, and calcium chloride. The chemical reaction is represented by the equation CaCO3 + 2HCl → CaCl2 + H2O + CO2.
The rate of the reaction is proportional to the number of collisions between reactant molecules. Increasing the concentration of hydrochloric acid increases the number of acid particles in the same volume of liquid, which increases the frequency of collisions. If equal amounts of marble chips react separately with different concentrations of hydrochloric acid, the amount of carbon dioxide gas produced remained the same in each case