In a solution acidified with HCI, `K_(2)Cr_(2)O_(7)` oxidises metallic tin (sin) to stannic chloride `(SnCI_(4))`. What volume of a decinormal `K_(2)Cr_(2)O_(7)` solution is required to oxidise 0.1 g of tin ?

Explanation

Oxidation reaction: `[SntoSn^(4+)+4e]xx3`
Reduction reaction :
`underline ([Cr_(2)O_(7)^(2-)+14H^(+)+6eto2Cr^(3+)+7H_(2)O]xx2)`
Net reaction
`3Sn+2Cr_(2)O_(7)^(2-)+28H^(+)toSn^(4+)+4Cr^(3+)+14H_(2)O`
In this reaction, equivalnet mass of Sn=`(118.7)/(4)=29.67`and the eqivalent mass of `K_(2)Cr_(2)O_(7)`
`("molecular mass "of K_(2)Cr_(2)O_(7))/(6)`
`therefore "2mol of" K_(2)Cr_(2)O_(7)-=`3mol of Sn
or, `(1)/(6)`mol of `K_(2)Cr_(2)O_(7)-=(1)/(4)`mol of sn
-=1 g- equivalnet of Sn -=29.67g of Sn or, 1000mL of 1 N `K_(2)Cr_(2)O_(7)`solution -=29.67g of Sn
or, 1000mL 0.1 `K_(2)Cr_(2)O_(7)`solution -=2.967g of sn
or 0.1 of Sn -`=(1000xx0.1)/(2.967)m`L. of 0.1N `K_(2)Cr_(2)O_(7)`solution is required to oxidise 0.1g of sn.