Kemija - 2009./10. ljeto - 4.

${\mathrm{S}\mathrm{O}}_4{}^{2-}\backslash mathrm\{SO\}\_\{4\}\{\; \}^\{2-\}$

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

${\mathrm{H}}_2{\mathrm{S}\mathrm{O}}_4\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{SO\}\_\{4\}$

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