Complete the equation for this reaction by inserting state symbols. $\text{Zn}(\ldots\ldots) + 2\text{HCl}(\ldots\ldots) \rightarrow \text{ZnCl}_2(\text{aq}) + \text{H}_2(\ldots\ldots)$
Deduce how long it takes from the start of the experiment to collect $39\,\text{cm}^3$ of hydrogen.
The student repeats the experiment with dilute hydrochloric acid of a higher concentration, while all other conditions remain unchanged. Draw a line on the grid in Fig. 3.1 to show how the volume of hydrogen changes when dilute hydrochloric acid with a higher concentration is used.
The student repeats the experiment at $30^\circ\text{C}$. All other conditions remain unchanged. Describe and explain, using collision theory, how the reaction rate changes when the temperature is $30^\circ\text{C}$.
A sample of hydrogen is placed in a gas syringe. The end of the gas syringe is then sealed so that no gas can escape. Explain, using kinetic particle theory, why decreasing the pressure in the gas syringe increases the gas volume when the temperature remains the same.