Kemija - 2013./14. jesen - 31.

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

samo ${\mathrm{O}\mathrm{H}}^{-}\backslash mathrm\{OH\}^\{-\}$

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