K2Cr2O7/H+\mathrm{K}_{2} \mathrm{Cr}_{2} \mathrm{O}_{7} / \mathrm{H}^{+}K2Cr2O7/H+
2,4−DNPH2,4-D N P H2,4−DNPH
[Ag(NH3]+\left[\mathrm{Ag}\left(\mathrm{NH}_{3}\right]^{+}\right.[Ag(NH3]+
PCI3\mathrm{PCI}_{3}PCI3