Kemija - 2020. ljeto, 10.

${\mathrm{N}\mathrm{a}}_2{\mathrm{C}\mathrm{r}\mathrm{O}}_4\backslash mathrm\{Na\}\_\{2\}\; \backslash mathrm\{CrO\}\_\{4\}$

${\mathrm{K}}_2{\mathrm{C}\mathrm{r}}_2{\mathrm{O}}_7\backslash mathrm\{K\}\_\{2\}\; \backslash mathrm\{Cr\}\_\{2\}\; \backslash mathrm\{O\}\_\{7\}$

$\mathrm{C}\mathrm{r}(\mathrm{O}\mathrm{H}{)}_3\backslash mathrm\{Cr\}(\backslash mathrm\{OH\})\_\{3\}$

${\mathrm{C}\mathrm{r}\mathrm{O}}_3\backslash mathrm\{CrO\}\_\{3\}$