Kemija - 2013./14. ljeto - 15.

${\mathrm{S}\mathrm{i}\mathrm{C}\mathrm{l}}_4\backslash mathrm\{SiCl\}\_\{4\}$

${\mathrm{P}}_4{\mathrm{O}}_6\backslash mathrm\{P\}\_\{4\}\; \backslash mathrm\{O\}\_\{6\}$

${\mathrm{C}\mathrm{l}}_2\mathrm{O}\backslash mathrm\{Cl\}\_\{2\}\; \backslash mathrm\{O\}$

${\mathrm{C}\mathrm{a}\mathrm{C}\mathrm{l}}_2\backslash mathrm\{CaCl\}\_\{2\}$