(a)[3]
Deduce the numbers of electrons, neutrons and protons in one atom of the chlorine isotope shown, $^{37}_{17}\text{Cl}$.
(b)[1]
State why chlorine is added to water during treatment.
(c(i))[2]
Complete the chemical equation for the reaction below.\n\n$\text{Cl}_2 + \ldots \text{KI} \rightarrow \ldots \text{KCl} + \text{I}_2$
(c(ii))[1]
Explain, in terms of halogen reactivity, why aqueous iodine does not react with aqueous potassium chloride.
(d(i))[2]
Complete the table by predicting:\n• the boiling point of fluorine\n• the density of liquid chlorine at its boiling point.
(d(ii))[2]
Predict the physical state of chlorine at $-105\,^\circ\text{C}$. Give a reason for your answer.