Question

9 A reaction between Br2 and KI is performed in the lab. To analyze the results of the reaction, the student adds hexane. Based on the observation, the student concludes Br2 is more active than 12 a) Write the net ionic equation of the reaction b) Describe what was observed in the reaction to be able to assess the relative activity of the halogens

Answer 1

(a)

2KI + Br₂$\rightarrow$ 2KBr + I₂

Net ionic reaction : answer:

2 I^-(aq) + Br₂(l) $\rightarrow$ I₂(s) .+ 2 Br^-(aq)

(b) Iodine is slightly soluble in water and gives a yellow solution. But solubility of iodine is more in organic solvent like hexane. The solution of iodine is violet in hexane. Appearance of violet color of organic layer(hexane) indicates the formation of iodine. The bromide ion has displaced the iodide ion from the salt. Hence Br₂ is more reactive than I₂ .