Kemija - 2014./15. ljeto - 33.

A. ${\mathrm{H}}_2\mathrm{O}\mathrm{i}\mathrm{H}\mathrm{P}\mathrm{O}{}_4{}^{2-}\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{O\}\; ~\backslash mathrm\{i\}\; ~\backslash mathrm\{HPO\}\{\; \}\_\{4\}\{\; \}^\{2-\}$

B. ${\mathrm{H}}_2{\mathrm{P}\mathrm{O}}_4^{-}\mathrm{i}{\mathrm{H}}_2\mathrm{O}\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{PO\}\_\{4\}^\{-\}\; \backslash mathrm\{~i\}\; ~\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{O\}$

C. ${\mathrm{H}\mathrm{P}\mathrm{O}}_4^{2-}\mathrm{i}{\mathrm{H}}_3{\mathrm{O}}^{+}\backslash mathrm\{HPO\}\_\{4\}^\{2-\}\; \backslash mathrm\{~i\}\; ~\backslash mathrm\{H\}\_\{3\}\; \backslash mathrm\{O\}^\{+\}$

D. ${\mathrm{H}}_3{\mathrm{O}}^{+}\mathrm{i}{\mathrm{H}}_2{\mathrm{P}\mathrm{O}}_4^{-}\backslash mathrm\{H\}\_\{3\}\; \backslash mathrm\{O\}^\{+\}\; \backslash mathrm\{~i\}\; ~\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{PO\}\_\{4\}^\{-\}$