[Partha Sarker]

Na₂SO₄ is a salt...well everybody knows it.But my question is this compound ionic or covalent?

the radical SO₄^2- is formed by covalent bonds.. But when Na₂SO₄ constructs 2 Na atoms give 2 e^- to 2 O₂ atoms.. So there is both ionic and covalent bonds.

So what should we call this compound an ionic one or a covalent one...

[Borek]

We treat it as an ionic salt (even if you are perfectly right about SO₄^2- containing covalent bonds). Trick is, SO₄^2- is so stable we rarely have to care about its internal structure, and most properties of Na₂SO₄ are defined by the presence of Na⁺ and the stable counterion.

[Partha Sarker]

We treat it as an ionic salt (even if you are perfectly right about SO₄^2- containing covalent bonds). Trick is, SO₄^2- is so stable we rarely have to care about its internal structure, and most properties of Na₂SO₄ are defined by the presence of Na⁺ and the stable counterion.

Do you mean "Counter Ion" by "counterion"

[Arkcon]

Do you mean "Counter Ion" by "counterion"

Apparently, it can be written both ways: http://en.wikipedia.org/wiki/Counterion

[Corribus]

@Partha

It is usually considered an ionic compound. However the sulfate ion is considered a "polyatomic ion", which is held together by covalent bonds.

http://en.wikipedia.org/wiki/Polyatomic_ion

(When I was learning general chemistry, we used the term "complex ion". But apparently this term is no longer in favor. Damn, that's when you know you're getting old - when terms you learned are being retired in favor of others...)

[Partha Sarker]

@Partha

It is usually considered an ionic compound. However the sulfate ion is considered a "polyatomic ion", which is held together by covalent bonds.

http://en.wikipedia.org/wiki/Polyatomic_ion

(When I was learning general chemistry, we used the term "complex ion". But apparently this term is no longer in favor. Damn, that's when you know you're getting old - when terms you learned are being retired in favor of others...)

So Radical=Polyatomic ion???