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

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements5 Marks
Question
Match the statements given in Column I with the oxidation states given in Column II.
 
Column I
 
Column II
(i)
Oxidation state of Mn in MnO2 is
(a)
+2
(ii)
Most stable oxidation state of Mn is
(b)
+3
(iii)
Most stable oxidation state of Mn in oxides is
(c)
+4
(iv) Characteristic oxidation state of lanthanoids is
(d)
+5
    (e) +7
✓

Answer

 
Column I
 
Column II
(i)
Oxidation state of Mn in MnO2 is
(c)
+4
(ii)
Most stable oxidation state of Mn is
(a)
 +2
(iii)
Most stable oxidation state of Mn in oxides is
(e)
+5
(iv) Characteristic oxidation state of lanthanoids is
(b)
+3

Explanation:

  1. Oxidation state of Mn in MnO2 is +4
  2. Most stable oxidation state of Mn is +2
  3. Most stable oxidation state of Mn in oxides is is +7
  4. Characteristic oxidation state of lanthanoid is +3

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