A displacement reaction occurs when chlorine water is added to a solution of potassium iodide. The observation made is that the solution turns:

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Question

A displacement reaction occurs when chlorine water is added to a solution of potassium iodide. The observation made is that the solution turns:

Accepted Answer

brown due to iodine formed — Chlorine displaces iodine from potassium iodide solution because chlorine is a more reactive halogen. The iodine produced causes the solution to turn brown (or orange-brown). The blue-black colour is only seen when iodine reacts with starch — without starch, the solution turns brown.

Answer

colourless due to chloride ions formed

Answer

blue-black due to iodine formed

Answer

green due to chlorine dissolved

Answer

brown due to iodine formed

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