[Starbright]

What mass of sodium Sulfate would contain 1.00 miles of oxygen?

The molar mass is 119.052 of Na2(So4) but since sulfate has 4 oxygens, can I divide my molar mass by 4?  Thanks for all your help.

[Hunter2]

Oxygen normaly exist as O₂. In Sodiumsulfat you have 4 O what means you can say 0.5 mol Persulfate equal to  1 mol O₂.

The rest is simple mathematics.

[mjc123]

The question is ambiguous, because it doesn't specify the form of "oxygen".
Taken literally, Na₂SO₄ "contains" precisely no O₂ (or S₈ or metallic Na). 1 mol contains 2 mol Na atoms, 1 mol S atoms and 4 mol O atoms. Therefore the answer I would give to your question (what mass contains 1 mole of oxygen) is the mass of 1/4 mol Na₂SO₄.
If decomposed to its constituent elements in their normal form, 1 mol Na₂SO₄ would yield 2 mol O₂.
With a question like this it is always best to be explicit in your answer about what form you are referring to, i.e. 1 mol O or 1 mol O₂. Then you may get marks for an anwer that is technically right even if it wasn't the answer the questioner wanted.

[Starbright]

Thank you so much.  Your answer makes sense.