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Redox Reactions

Short Answer Type

111.

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?
$straight K bottom enclose straight I subscript 3$

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112.

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?
$straight H subscript 2 bottom enclose straight S subscript 4 end enclose straight O subscript 6$

108 Views

113.

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?
$bottom enclose Fe subscript 3 end enclose straight O subscript 4$

98 Views

114.

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?

$bold space bold space bottom enclose bold C bold H subscript bold 3 bottom enclose bold C bold H subscript bold 2 bold OH$

121 Views

115.

What are the oxidation number of the underlined elements in each of the following and how do you rationalise your results?
$bottom enclose straight C straight H subscript 3 bottom enclose straight C OOH$

130 Views

Long Answer Type

116.
Calculate the oxidation number of sulphur, chromium and nitrogen in H₂SO₅, $space space Cr subscript 2 straight O subscript 7 superscript 2 minus end superscript$ and $space space NO subscript 3 superscript minus$ Suggest structure of these compounds. Count for the fallacy.

(i) Oxidation number of S in H₂SO₅By conventional method
2 x 1 + x + 5 x (-2) = 0
or 2 + x - 10 = 0 or x = + 8 (wrong)
But this cannot be true as maximum oxidation number for sulphur cannot exceed +6. The exceptional value is due to the fact that two oxygen atoms in H₂SO₅ show peroxide linkage.

This is wrong because maximum oxidation of Cr cannot be more than +6 since it has only six electrons (3d⁵ 4s¹) to take part in bond formation. Actually, four out of five oxygen atoms in CrO₅ are present in peroxide linkage.
By chemical bonding method.