Kemija - 2012./13. jesen - 7.

A. $\mathrm{N}\mathrm{a}\backslash mathrm\{Na\}$

B. ${\mathrm{S}}^{2-}\backslash mathrm\{S\}^\{2-\}$

C. ${\mathrm{C}\mathrm{l}}^{-}\backslash mathrm\{Cl\}^\{-\}$

D. ${\mathrm{N}\mathrm{a}}^{+}\backslash mathrm\{Na\}^\{+\}$