Расположите формулы приведенных оксидов по возрастанию в них массовых долей металлов

Mr(Na2O) = Mr = Ar(O) + 2Ar(Na) = 1 * 16 + 2 * 23 = 62

w(Na) = 2Ar(Na) / Mr = 46 / 62 = 0.7419 = 74.19%

Mr(BaO) = Mr = Ar(O) + Ar(Ba) = 1 * 16 + 1 * 137 = 153

w(Ba) = Ar(Ba) / Mr = 137 / 153 = 0.8954 = 89.54%

Mr(CrO) = Mr = Ar(O) + Ar(Cr) = 1 * 16 + 1 * 52 = 68

w(Cr) = Ar(Cr) / Mr = 52 / 68 = 0.7647 = 76.47%

Mr(MnO2) = Mr = 2Ar(O) + Ar(Mn) = 2 * 16 + 1 * 55 = 87

w(Mn) = Ar(Mn) / Mr = 55 / 87 = 0.6322 = 63.22%

Mr(PbO2) = Mr = 2Ar(O) + Ar(Pb) = 2 * 16 + 1 * 207 = 239

w(Pb) = Ar(Pb) / Mr = 207 / 239 = 0.8661 = 86.61%

MnO2, Na2O, CrO, PbO2, BaO