[EvilFrog (OP)]

why barium carbonate is much more poisonous than barium sulfate?

[lightarrow]

why barium carbonate is much more poisonous than barium sulfate?

Because, even if is water insoluble, it reacts with HCl inside the stomach, producing Ba(Cl)₂ which is water soluble and so it forms Ba²⁺ ions, which are the real toxic chemical.
BaSO₄ instead is water insoluble and don't dissolve enough in HCl to form a toxic concentration of Ba²⁺ ions. To dissolve it significantly with an acid you would need a much stronger acid, for example concentrated sulfuric acid, and, luckily, we don't have it inside our stomach  [].

Of course all of this has a meaning if we consider oral ingestion only of those chemicals...

[EvilFrog (OP)]

Yup! thanks for reply.

[EvilFrog (OP)]

Why change "sulphate" into "sulfate"?

[lightarrow]

Why change "sulphate" into "sulfate"?

Because I never remember how to write it...
P.S. forgive a poor italian man []

[EvilFrog (OP)]

Nvr mind, lightarrow. Then, who else can answer me? Chris? Bored chemist?