Kemija - 2020. jesen, 29.

A. ${\mathrm{O}\mathrm{H}}^{-}\backslash mathrm\{OH\}^\{-\}$  i  ${\mathrm{H}}_2\mathrm{O}\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{O\}$

B. ${\mathrm{H}\mathrm{C}\mathrm{O}}_3^{-}\backslash mathrm\{HCO\}\_\{3\}^\{-\}$  i  ${\mathrm{O}\mathrm{H}}^{-}\backslash mathrm\{OH\}^\{-\}$

C. ${\mathrm{H}}_2\mathrm{O}\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{O\}$ i ${\mathrm{H}}_2{\mathrm{C}\mathrm{O}}_3\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{CO\}\_\{3\}$

D. ${\mathrm{H}}_2{\mathrm{C}\mathrm{O}}_3\backslash mathrm\{H\}\_\{2\}\; \backslash mathrm\{CO\}\_\{3\}$ i ${\mathrm{H}\mathrm{C}\mathrm{O}}_3{}^{-}\backslash mathrm\{HCO\}\_\{3\}\{\; \}^\{-\}$