The graph gives the volume of hydrogen gas produced at $20\,^{\circ}\text{C}$ as the reaction goes on. State how much time passes from the start of the experiment before $18\,\text{cm}^3$ of hydrogen gas is collected.
The experiment is carried out again at $30\,^{\circ}\text{C}$. All the other conditions remain unchanged. Draw a line on the grid to show how the volume of hydrogen gas changes with time when the reaction is performed at $30\,^{\circ}\text{C}$.
Describe and explain, using ideas about collisions between particles, how the rate of the reaction changes when the temperature of the reaction mixture is increased. All the other conditions stay the same.
Describe and explain, using ideas about collisions between particles, how the rate of the reaction changes when larger pieces of iron are used. All the other conditions stay the same.
Calculate the maximum volume, in $\text{dm}^3$, of hydrogen produced when $3.36\,\text{g}$ of iron react with excess dilute sulfuric acid at room temperature and pressure. Give your answer to three significant figures.
Concentrated sulfuric acid is an oxidising agent. Describe a test for oxidising agents. method result