Iodine reacts with chlorine to form iodine(I) chloride, ICl. I₂ + Cl₂ → 2ICl Iodine(I) chloride reacts in a similar way to both iodine and chlorine.

1. (a)Sodium reacts with iodine(I) chloride. Construct the equation for the reaction between sodium and iodine(I) chloride.[1]
2. (b)Iodine(I) chloride reacts with ethene. Draw the structure of the product of this reaction. Show all of the atoms and all of the bonds.[1]
3. (c)Iodine(I) chloride reacts with ethane in the presence of ultraviolet light. Deduce the type of reaction that takes place and construct an equation for this reaction. type of reaction .......................................................................................... equation ....................................................................................................[2]
4. (d)Draw a 'dot-and-cross' diagram to show a molecule of iodine(I) chloride. Only show the outer shell electrons.[1]
5. (e)(i)Iodine(I) chloride reacts with chlorine to form iodine(III) chloride. This reaction is investigated at 200°C in a sealed container. A dynamic equilibrium mixture is established. ICl(g) + Cl₂(g) ⇌ ICl₃(g) ICl(g) is a dark brown gas. ICl₃(g) is a yellow gas. What is meant by the term dynamic equilibrium? Refer to both rate of reaction and concentration in your answer.[3]
6. (e)(ii)The pressure of the equilibrium mixture is increased. The temperature is kept at 200 °C. Predict and explain what will happen to the colour of the equilibrium mixture.[2]

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