Kalsiy sulfat, temir (II) sulfat va xrom (III) sulfat kristallogidratl

A) 60,4

121. (v13-133-7) Kalsiy sulfat, temir (II) sulfat va xrom (III) sulfat kristallogidratlari aralashmasi tarkibida vodorodning massa ulushi 3,56% metallarning massa ulushlari yigindisi 20% bolsa, shu aralashmadagi kislorodni massa ulushini (%) aniqlang? A) 60,4 B) 32,0 C)63,3
D) 64,0