Назовите валентность соединений:
а)Cl2O7, Cl2O, ClO2;
б)FeCl3, FeCl2;
в)MnS, MnO2, MnF4, MnO, MnCl4;
г)Cu2O, Mg2Si, SiCl4, Na3N, FeS.

Cl2(VII)O7(II), CL2(I)O(II), CI(IV)O2(II)Fe(III)Cl3(I), Fe(II)Cl2(I)Mn(II)S(II), Mn(IV)O2(II), Mn(IV)F(I), Mn(II)O(II), Mn(IV)Cl4(I)Cu2(I)O(II), Mg2(IV)Si(II), Si(IV)CI4(I), Na3(I)N(III), Fe(II)S(II).