мол. H3PO4
w(H) =?
w(P) =?
w(O) =?
—————————
Mr(H3PO4) = Ar(H) × 3 + Ar(P) + Ar(O) × 4
w(H) = Ar(H) × 3 / Mr(H3PO4) * 100%
w(H) = Ar(P) / Mr(H3PO4) * 100%
w(O) = Ar(O) × 4 / Mr(H3PO4) * 100%
Mr(H3PO4) = 1 × 3 + 31 + 16 × 4 = 98 г/моль
w(H) = 1 × 3 / 98 * 100% ≈ 3%
w(H) = 31 / 98 * 100% ≈ 32%
w(O) = 16 × 4 / 98 * 100% ≈ 65%
мол. H3PO4
w(H) =?
w(P) =?
w(O) =?
—————————
Mr(H3PO4) = Ar(H) × 3 + Ar(P) + Ar(O) × 4
w(H) = Ar(H) × 3 / Mr(H3PO4) * 100%
w(H) = Ar(P) / Mr(H3PO4) * 100%
w(O) = Ar(O) × 4 / Mr(H3PO4) * 100%
Решение:Mr(H3PO4) = 1 × 3 + 31 + 16 × 4 = 98 г/моль
w(H) = 1 × 3 / 98 * 100% ≈ 3%
w(H) = 31 / 98 * 100% ≈ 32%
w(O) = 16 × 4 / 98 * 100% ≈ 65%
ответ: w(H) = 3%; w(P) = 32%; w(O) = 65%