a)
\(2Br^{-1} \rightarrow Br_2^0+2e\) | `xx1` |
\(Cl_2^0+2e\rightarrow2Cl^{-1}\) | `xx1` |
`2NaBr + Cl_2 -> 2NaCl + Br_2`
b)
\(2Fe^{+3}+6e\rightarrow2Fe^0\) | `xx1` |
\(C^{+2}\rightarrow C^{+4}+2e\) | `xx3` |
\(Fe_2O_3+3CO\xrightarrow[]{t^o}2Fe+3CO_2\)
c)
\(C^{+2}\rightarrow C^{+4}+2e\) | `xx5` |
\(2I^{+5}+10e\rightarrow2I_2^0\) | `xx1` |
d)
\(Cr^{+3}\rightarrow Cr^{+6}+3e\) | `xx2` |
\(Br^0_2+2e\rightarrow2Br^{-1}\) | `xx3` |
\(2Cr\left(OH\right)_3+3Br_2+10OH^-\rightarrow2CrO_4^{2-}+6Br^-+8H_2O\)
e)
\(Mn^{+7}+5e\rightarrow Mn^{+2}\) | `xx2` |
\(C^{+2}\rightarrow C^{+4}+2e\) | `xx5` |
\(6H^++2MnO_4^-+5HCOOH\rightarrow2Mn^{2+}+8H_2O+5CO_2\uparrow\)