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The d & f Block Elements — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements5 Marks
Question
Answer the following questions:
Write balanced equations to represent what happens when.
  1. Cu2+ is treated with KI.
  2. Acidified potassium dichromate solution is reacted with iron (II) solution. (ionic equation).
✓

Answer

  1. $2\text{Cu}^{2+}4\text{I}^-\xrightarrow{\ \ \ \ \ \ \ \ }2\text{Cr}^{3+}+7\text{H}_2\text{O}$

$\text{Cr}_2\text{O}^{2-}_7+14\text{H}^++6\text{e}^-\xrightarrow{ \ \ \ \ \ \ \ \ }2\text{Cr}^{3+}+7\text{H}_2\text{O}$

  1. $\text{Fe}^{2+}\xrightarrow{\ \ \ \ \ \ \ \ \ }\text{Fe}^{3+}+\text{e}^-]\times6$

$\text{Cr}_2\text{O}^{2-}_+6\text{Fe}^{2+}+14\text{H}^+\xrightarrow{\ \ \ \ \ \ \ \ \ }2\text{Cr}^{3+}+6\text{Fe}^{3+}+7\text{H}_2+\text{O}$

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