Al (NO3)3
Comp. procentuala se poate calcula prin: - raport de masa
- masa molara
M=AAl + 3AN +9O
M=27 + 3.14 + 9. 16=213------> 213 g/moli
213 g Al (NO3)3----------27gAl--------42g N---------144g O
100 g------------------------------x---------------y-------------z
x=100.27 : 213=12,68 % Al
y=100.42 :213=19,72 % N
z=100.144 : 213=67,6% O