а) Cu, N2, Ca, H2, S8, O2.
б) Al2O3, CaC2, Li3N, Al4C3, Ca3N2, N2O, CaF2, N2O5, Mg2Si, PbO2. в) Pb(NO3)2, K2CO3, Na2SiO3, Ca(NO3)2, Mg3(PO4)2, C3H7O2, Al2(SO4)3, Na2CO3.