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Redox Reactions

Question
CBSEENCH11006729

Why does the following reaction occur?bold XeO subscript bold 6 superscript bold 4 bold minus end superscript bold left parenthesis bold aq bold right parenthesis bold space bold plus bold 2 bold F to the power of bold minus bold left parenthesis bold aq bold right parenthesis bold space bold plus bold 6 bold H to the power of bold plus bold left parenthesis bold aq bold right parenthesis
bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold rightwards arrow bold XeO subscript bold 3 bold left parenthesis bold g bold right parenthesis bold space bold plus bold F subscript bold 2 bold left parenthesis bold g bold right parenthesis bold plus bold 3 bold H subscript bold 2 bold O bold left parenthesis bold l bold right parenthesis

conclusion about the compound Na4XeO6 (of which XeO64– is a part) can be drawn from the reaction ?






Solution

Writing the oxidation number of all the atoms above their respective symbols, bold Xe with bold plus bold 8 on top bold O subscript bold 6 superscript bold 4 bold minus end superscript bold left parenthesis bold aq bold right parenthesis bold space bold plus bold 2 stack bold F to the power of bold minus with bold minus bold 1 on top bold left parenthesis bold aq bold right parenthesis bold plus bold 6 bold H to the power of bold plus bold left parenthesis bold aq bold right parenthesis end exponent
bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold space bold rightwards arrow bold Xe with bold plus bold 6 on top bold O subscript bold 3 bold left parenthesis bold g bold right parenthesis bold plus stack bold space bold F subscript bold 2 with bold 0 on top bold left parenthesis bold g bold right parenthesis bold plus bold 3 bold H subscript bold 2 bold O bold left parenthesis bold l bold right parenthesis
      
Since the O.N.of F increases from -1 in F- to zero in F2 and therefore it is oxidised and hence acts as a reductant. The O.N. of Xe decreases from +8 in XeO64- to 6+ in XeOand therefore it is reduced and acts as an oxidant. This reaction occurs since Na4XeO64- (or XeO64- is a stronger oxidant than F2).