Balance the following redox equations by the ion-electron method. (Use the lowest possible coefficients.)
(c) CN - + MnO4- +H2O>>>CNO- + MnO2 + OH - (in basic solution)
(d) Br2 + OH ->>>> BrO3- + Br - + H2O (in basic solution)
redox equations
2008-04-13 4:24 pm
回答 (2)
2008-04-13 6:00 pm
✔ 最佳答案
In basic solutions, OH- and H2O are used to balance the equations.==========
(c)
CN- + 2OH- → CNO- + H2O + 2e- …… (c1)
MnO4- + 2H2O + 3e- → MnO2 + 4OH- …… (c2)
To cancel all e-, (c1)x3 + (c2)x2:
3CN- + 2MnO4- + H2O → 3CNO- + 2MnO2 + 2OH-
=========
(d)
Br2 + 12OH- → 2BrO3- + 6H2O + 10e- …… (d1)
Br2 + 2e- → 2Br- …… (d2)
To cancel all e-, (d1) + (d2)x5:
6Br2 + 12OH- → 2BrO3- + 10Br- + 6H2O
To make the lowest coefficients, both sides divided by 2:
3Br2 + 6OH- → BrO3- + 5Br- + 3H2O
2008-04-13 5:19 pm
3 CN- + 2 MnO4- + H2O >>> 3 CNO- + 2 MnO2 + 2 OH-
7 Br2 + 12 OH- >>> 2 BrO3 + 12 Br- + 6 H2O
7 Br2 + 12 OH- >>> 2 BrO3 + 12 Br- + 6 H2O
收錄日期: 2021-04-25 19:45:02
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