notam cu
x = nr. moli Na2O
y = nr. moli CaO
stim Na2O = 62 g/mol, CaO = 56 g/mol
62x + 56y = 18 g amestec
100% amestec................................ 26,666% O
(62x + 56y) g amestec ................ (16x+16y) g O
(62x + 56y)= 3,75.(16x+16y)
=> 2x = 4y
=> raportul molar x : y = 1 : 2
=> 62x + 56y = 18 => y = 0,1 moli Na2O
x = 0,2 moli CaO
=> 0,2x62 = 12,4 g Na2O
=> 0,1x56 = 5,6 g CaO