Calculați cele două tabele de jos
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2.Al are valenta 3; S are valenta 2
Mg are valenta 2; I are valenta 1
Ca are valenta 2; Cl are valenta 1
N are valenta 5; O are valenta 2
C are valenta 4; O are valenta 2
3.Carbonat de calciu
Clorura de bariu
Azotat de fer(II)
Oxidde sulf