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give a list of the halogens which will oxidise dichromium

standard electrode potentials for chromium(III) changing to chromium(II) and for chromium(VI) changing to chromium(III) are given below. Cr3+ + e– Cr2+ E = –0.41V
1/2Cr2 O72–+ 7H+ + 3e– Cr3+ + 2 7 H2O E = +1.33V
list the halogens which will oxidise dichromium(II) to chromium(III) but not to chromium (VI),
electrode reaction E /V
1/2F2 + e– F– +2.87
1/2Cl2 + e– Cl– +1.36
1/2 Br2 + e– Br– +1.07
1/2 I2 + e– I– +0.54

why is the answer iodine and bromine?
but the question before asked what halogens oxidisise dichromium to chromium(III) and the answer was all of the halogens. how do u even work this question out??
The electrode potential of the halogen needs to lie between -0.41V and 1.33V so Br2 and I2
Original post by usernamenew
standard electrode potentials for chromium(III) changing to chromium(II) and for chromium(VI) changing to chromium(III) are given below. Cr3+ + e– Cr2+ E = –0.41V
1/2Cr2 O72–+ 7H+ + 3e– Cr3+ + 2 7 H2O E = +1.33V
list the halogens which will oxidise dichromium(II) to chromium(III) but not to chromium (VI),
electrode reaction E /V
1/2F2 + e– F– +2.87
1/2Cl2 + e– Cl– +1.36
1/2 Br2 + e– Br– +1.07
1/2 I2 + e– I– +0.54

why is the answer iodine and bromine?
but the question before asked what halogens oxidisise dichromium to chromium(III) and the answer was all of the halogens. how do u even work this question out??

The species in question are :
chromium(II)
dichromate(VI)

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