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

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
Complete the following chemical equations:
  1. $\text{MnO}_{4}^{-}+\text{C}_{2}\text{O}_{4}^{2-}+\text{H}+\rightarrow$
  2. $\text{KMnO}_{4}\xrightarrow{\text{heated}}$
  3. $\text{Cr}_{2}\text{O}_{4}^{2-}+\text{H}_{2}\text{S}+\text{H}^{+}+\rightarrow$
✓

Answer

  1. $\text{5C}_{2}\text{O}_{4}^{2-}+\text{2MnO}_{4}^{-}+\text{16H}^{4+}\xrightarrow{\ \ \ \ \ }\ \text{2Mn}^{2+}+\text{8H}_{2}\text{O}+\text{10CO}_{2}.$
  2. $\text{KMnO}_{4}\xrightarrow{\text{heat}}\ \text{K}_{2}\text{MnO}_{2}+\text{MnO}_{2}+\text{O}_{2}$
  3. $\text{Cr}_{2}\text{O}_{7}^{2-}+\text{3H}_{2}\text{S}+\text{8H}^{+}\xrightarrow{\ \ \ \ \ \ }\ \text{2Cr}^{3+}+\text{3S}+\text{7H}_{2}\text{O}$.

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