1) Mr(KNO) = 39 + 14 + 16 = 69
W(E)= (n • Ar(E)) / Mr(сполуки) • 100%
W(K) = (1 • 39)/69 = 0,57 • 100% = 57%
W(N) = (1 • 14)/69 = 0,2 • 100% = 20%
W(O) = (1 • 16)/69 = 0,23 • 100% = 23%
2) Mr(FeCl3) = 56 + 3•35,5 = 162,5
W(Fe) = (1•56)/162,5 = 0,34 • 100% = 34%
W(Cl) = (3•35,5)/162,5 = 0,66 • 100% = 66%
