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Transcription of this question: This question is about peroxides.(a)(b)Suggest why many chemicals, including hydrogen peroxide, are kept in brown bottlesinstead of clear colourless bottles.Hydrogen peroxide decomposes to water and oxygen when a catalyst such aspotassium iodide, KI, is added.KI (aq)2H202 (aq) 02 (g) + 2H20 (l)In a laboratory experiment solutions of potassium iodide and hydrogen peroxidewere mixed and the volume of oxygen generated was recorded. The volume wasadjusted to O at t = O.o5 10 15 20 25The data for the first trial is given below.Time I s100700Volume of 02 (g) I cm32.56.511.015.0Plot a graph on the axes below and frorn it determine the average rate Offormation Of oxygen gas in cm3 02 (g) s1513100 100 200 300 400 500 600 700Time / sAverage rate of reaction:(ii)(iii)Additional experiments were carried out at an elevated temperature. On the axesbelow, sketch Maxwell—Boltzmann energy distribution curves at two temperaturesTl and Ta, where T 2 > T,.[2]Kinetic energyApart from a greater frequency of collisions, explain, by annotating your graphs in(b)(ii), why an increased temperature causes the rate of reaction to increase.[2](iv) Mn02 is another possible catalyst for the reaction. State the IIJPAC name for Mn02.[1](c)(d)Comment on why peracetic acid, CH3COOOH, is always sold in solution with ethanoicacid and hydrogen peroxide.H202 (aq) + CH3COOH (aq) CH3COOOH (aq) + (l)Sodium percarbonate, 2Na2C03•3H202, is an adduct of sodium carbonate andhydrogen peroxide and is used as a cleaning agent.Mr (2Na2COs•3H202) = 314.04Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate,giving your answer to two decimal places.[2]

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