These alkali metal germanides, stannides, and plumbides may be produced by reducing germanium, tin, and lead with sodium metal in liquid ammonia.
ðiːz ˈælkəlˌaɪ mˈɛɾəl dʒˈɜːmɐnˌaɪdz, stˈænaɪdz, ænd plˈʌmbaɪdz mˈeɪ biː pɹədˈuːst baɪ ɹᵻdˈuːsɪŋ dʒɜːmˈeɪniəm, tˈɪn, ænd lˈiːd wɪð sˈoʊdiəm mˈɛɾəl ɪn lˈɪkwɪd æmˈoʊniə.