An investigation was carried out to measure the rate of reaction between solid calcium carbonate (CaCO3CaCO_3CaCO3) and dilute nitric acid (HNO3HNO_3HNO3).
In the first set of experiments, 3.0 g of large marble chips were reacted with 50 cm3 of 0.50 mol dm-3 nitric acid. This was repeated using 3.0 g of the same large chips with 50 cm3 of 1.50 mol dm-3 nitric acid.
In the second set of experiments, the procedures were repeated using 3.0 g of fine calcium carbonate powder instead of the large marble chips.
In each experiment, the decrease in mass of the flask and its contents after 2 minutes was recorded, using the experimental setup shown below.
The results of the investigation are shown in the table below.
| Concentration of nitric acid (mol dm−3\text{mol dm}^{-3}mol dm−3) | Decrease in mass from large marble chips (g\text{g}g) | Decrease in mass from fine calcium carbonate powder (g\text{g}g) |
|---|---|---|
| 0.50 | 0.15 | 0.48 |
| 1.50 | 0.45 | 1.42 |
Explain, in terms of particle collision theory, how these results show the effect of the surface area (particle size) of the calcium carbonate and the effect of the concentration of the nitric acid on the rate of this reaction.
