Students investigate the reaction between a 2.0 cm2.0\text{ cm}2.0 cm strip of magnesium ribbon and excess dilute hydrochloric acid. They want to find out how temperature changes the rate of reaction. They measure the time taken for the magnesium ribbon to completely dissolve (reaction time) at various temperatures. The table shows their results:
| Temperature (∘C^\circ\text{C}∘C) | Reaction Time (s\text{s}s) |
|---|---|
| 15 | 180 |
| 25 | 90 |
| 35 | 50 |
| 45 | 32 |
| 55 | 22 |
A student plots these results on a grid and draws a smooth curve of best fit.
a.[1]
Use the curve of best fit to determine the reaction time at 30∘C30^\circ\text{C}30∘C.
b.[1]
State what happens to the rate of reaction as the temperature of the acid increases.
c.[3]
Explain this change in reaction rate in terms of particle collision theory.