a.
Al(OH)3 = hidroxid de aluminiu
M.Al(OH)3 = 27+(16+1)3 = 78 g/mol
1 mol ...................... 78 g
x moli ................... 130000 g
= 1666,67 moli Al(OH)3
1 mol Al(OH)3 ................ 3x6,022x10la23 anioni (OH)-
1666,67 moli ...................... n = 3,011x10la 27 anioni (OH)-
b.
Fe(OH)3 = hidroxid feric
M.Fe(OH)3 = 56+(16+1)3 = 107 g/mol
1 mol Fe(OH)3 ......................... 107 g
x moli ..................................... 8560 g
= 80 moli
1 mol Fe(OH)3 ............... 1x6,022x10la23 cationi Fe(3+)
80 moli .............................. n = 4,82x10la25 cationi Fe(3+)