Explain why $\text{MnO}_2(s)$ is called an oxidising agent in this reaction. Use oxidation numbers in your answer.
State one observation you would make during this reaction.
The halogens chlorine, bromine and iodine are all volatile elements. State and explain how volatility changes down Group 17.
Write an equation for the reaction of chlorine with cold aqueous sodium hydroxide, $\text{NaOH}$. Explain why it is a disproportionation reaction.
One product from the reaction of chlorine with hot aqueous sodium hydroxide is different from the products in part (c)(i). Identify the compound formed in this reaction that is different from the one formed in the reaction in part (c)(i).
State and explain how chlorine is used in water purification.
Under certain conditions, chlorine undergoes a free-radical substitution reaction with ethane. State the conditions needed to start this reaction.
Write the overall equation for this free-radical substitution reaction.