Kemija - 2012./13. jesen - 37.

${\mathrm{M}\mathrm{n}\mathrm{O}}_4{}^{-}\backslash mathrm\{MnO\}\_\{4\}\{\; \}^\{-\}$

${\mathrm{C}}_2{\mathrm{O}}_4{}^{2-}\backslash mathrm\{C\}\_\{2\}\; \backslash mathrm\{O\}\_\{4\}\{\; \}^\{2-\}$

${\mathrm{H}}_2\mathrm{O}\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{O\}$

${\mathrm{H}}_3{\mathrm{O}}^{+}\backslash mathrm\{H\}\_\{3\}\; \backslash mathrm\{O\}^\{+\}$