1. Определите валентность элементов в соединениях: a) NaH, CaH2, NH3, HCl, H2S, PH3, SiH4, H2O б) Na2O, CaO, Al2O3, SiO2, CO, CO2, SO2, SO3, Cl2O, Cl2O7 в) Na3N, Li3P, CaS, Mg3N2, AlP, AlN, Al4Si3, MgCl2, CaF2, AlCl3, Al2S3

a) NaH (Na - I, H - I), CaH2 (Ca - II, H - I), NH3 (N - III, H - I), HCl (H - I, Cl - I), H2S (H - I, S - II), PH3 (P - III, H - I), SiH4 (Si - IV, H - I), H2O (H - I, O - II) б) Na2O (Na - I, O - II), CaO (Ca - II, O - II), Al2O3 (Al - III, O - II), SiO2 (Si - IV, O - II), CO (C - II, O - II), CO2 (C - IV, O - II), SO2 (S - IV, O - II), SO3 (S - VI, O - II), Cl2O (Cl - I, O - II), Cl2O7 (Cl - VII, O - II) в) Na3N (Na - I, N - III), Li3P (Li - I, P - III), CaS (Ca - II, S - II), Mg3N2 (Mg - II, N - III), AlP (Al - III, P - III), AlN (Al - III, N - III), Al4Si3 (Al - III, Si - IV), MgCl2 (Mg - II, Cl - I), CaF2 (Ca - II, F - I), AlCl3 (Al - III, Cl - I), Al2S3 (Al - III, S - II)