Balance the following chemical reactions (by ion electron method)
(a) `C_(2)H_(5)OH+MnO_(4)^(Ө) rarr CH_(3)COO^(Ө) +MnO_(2)+H_(2)O+overset(Ө) (OH)`
(b) `[Fe(CN)_(6)]^(3-_ + N_(2)H_(4) + overset(Ө) (OH)rarr [Fe(CN_(6))]^(4-) + N_(2)+H_(2)O`
(c ) `CN^(Ө) + MnO_(4)^(Ө) +H_(2)O rarr MnO_(2)+CNO^(Ө) + overset(Ө) (OH)`
(d) `CuO+NH_(3) rarr Cu+N_(2)+H_(2)O`
(e) `HI+HNO_(3) rarr I_(2) + NO+H_(2)O`
(f) `H_(2)S+SO_(2)rarrS+H_(2)O`

Answer

A

Explanation

a. Basic medium
`4H_(2)O+cancel(3e^(-))+MnO_(4)^(ө)rarrMnO_(2)+2H_(2)O+4overset(ө)OH]xx4`
`{:(x-8,-1,x-4,=,0),(x,7,x,=,4):}`
`5overset(ө)OH+H_(2)O+C_(2)H_(5)OHrarrCH_(3)COO^(ө)+cancel(4e^(-))+5H_(2)O]xx3`
` {:(2x+6-2=0,,2x+3-4=-1,,),(x=7,-,2x=0,,):}/ul(4MNO_(4)^(ө)+3C_(2)H_(5)OHrarr4MnO_(2)+3CHOO^(ө)+overset(ө)OH+4H_(2)O`
b. Basic medium
`4overset(ө)OH_N_(2)H_(4)rarrN_(2)+cancel(4e^(-))+4H_(2)O`
`{:(2x+4=0,,2x=-0,,),(2x=-4,-,2x=0,,):}`
`cancel(e^(-))+[Fe(CN)_(6)]^(3)rarr [Fe(overset(-1)(CN_(6)))]^(4)]xx4`
`ulbar(4overset(ө)OH+N_(2)H_(4)+4[Fe(CN)_(6)]^(3-)rarrN_(2)+4[Fe(CN)_(6)]^(4-)+4H_(2)O`
c. `4H_(2)Ocancel(3e)+MnO_(4)^(ө)rarrMnO_(2)+2H_(2)O+4overset(ө)OH]xx2`
`{:(x-8=-1,x-4=0,,,),(x=7,x=4,,,):}`
`2overset(ө)OH+H_(2)O+CN^(ө)rarrCNO^(ө)+cancel(2e)+2H_(2)O]xx3`
`{:(x-3=-1,x-3=-2=-1,,,),(x=2,x=4,,,):}`
`ulbar(H_(2)O+2MnO_(4)+3CN^(ө)rarr2MnO_(2)+3CNO^(ө)+2overset(ө)OH)`
d. `2NH_(3)-ltN_(2)+cancel(6e^(-))+cancel(6H^(o+))`
`2x+6=0, 2x=0`
`2x= -6`
`cancel(2H^(o+))+cancel(2e^(-))+CuOrarrCu+H_(2)O]xx3`
`x-2=0, x=0`
`x=2`
`ulbar(2NH_(3)+3CuOrarrN_(2)+3Cu+3H_(2)O)`
e. `2HIrarrI_(2)+cancel(2e^(-))+cancel(2H^(o+))]xx3`
`2+2x=0,2x=0`
`2x= -2`
`3H^(o+)+3e^(-)+HNO_(3) -lt NO+2H_(2)O]xx2`
`1+x-6=0, x-2=0`
`x=5, x=2`
`ulbar(6HI+2HNO_(3)rarr3I_(2)+2NO+4H_(2)O)`
f. `H_(2)SrarrS+cancel(2^(e-))+cancel(2H^(o+))]xx2`
`2+x=0, x=0`
`x=-2`
`calcel(4H^(o+))+cancel(4e^(-))+SO_(2)rarrS+2H_(2)O`
`x-4=0, x=0`
`ulbar(2H_(2)S+SO_(2)rarr3S+2H_(2)O`.