The end point of a potassium dichromate(VI) titration isn't as easy to see as the end point of a potassium manganate(VII) one. However, the color is made difficult by the strong green also present. This gives a violet-blue color in the presence of excess potassium dichromate(VI) solution. There are several such indicators - such as diphenylamine sulfonate. These change color in the presence of an oxidising agent. Expert Answer 100 (1 rating) ANSWER:305.80504amu FORMULA WEIGHT OF Chromium (II) iodide (CrI2) Cation Cr2+ Atomic weight 51.9961 number of ions View the full answer Transcribed image text: Complete the table below for calculating the formula weight of the ionic compound chromium (II) fodide, Crlz. With potassium dichromate(VI) solution you have to use a separate indicator, known as a redox indicator. Unfortunately potassium dichromate(VI) solution turns green as you run it into the reaction, and there is no way you could possibly detect the color change when you have one drop of excess orange solution in a strongly colored green solution. As soon as you add as much as one drop too much, the solution becomes pink - and you know you have reached the end point. As you run the potassium manganate(VII) solution into the reaction, the solution becomes colorless. Potassium manganate(VII) titrations are self-indicating. The main disadvantage lies in the color change.That means that you don't get unwanted side reactions with the potassium dichromate(VI) soution. KNO2 - Potassium nitrite SF6 - Sulfur hexafluoride CrPO4 - Chromium(III) phosphate (There is no compoun like Cr(PO2)2 ) NiCO3 - Nickel(II) carbonate (There is no compound like NiCO2 ) CCl4 - Carbon tetrachloride. Potassium manganate(VII) oxidises chloride ions to chlorine potassium dichromate(VI) isn't quite a strong enough oxidising agent to do this. chromium (II) iodide chromium (III) chloride cobalt (II) bromide copper (II) oxide. Potassium dichromate(VI) can be used in the presence of chloride ions (as long as the chloride ions aren't present in very high concentration).That isn't true of potassium manganate(VII). That means that it can be made up to give a stable solution of accurately known concentration. Potassium dichromate(VI) can be used as a primary standard.There are advantages and disadvantages in using potassium dichromate(VI). You will see that the chromium(III) sulfate and potassium sulfate are produced in exactly the right proportions to make the double salt. Home » Chemistry » Chromium (II) Iodide Name: Chromium (II) Iodide Alias: Chromous Iodide Formula: CrI2 Molar Mass: 305.
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