Answer:
Is not possible to make a buffer near of 7.
Optimal pH for sulfate‑based buffers is 2.
Explanation:
The dissociations of H₂SO₄ are:
H₂SO₄ ⇄ H⁺ + HSO₄⁻ pka₁ = -10
HSO₄⁻ ⇄ H⁺ + SO₄²⁻ pka₂ = 2.
The buffering capacity is pka±1. That means that for H₂SO₄ the buffering capacity is in pH's between -11 and -9 and between 1 and 3, having in mind that pH's<0 are not useful. For that reason, is not possible to make a buffer near of 7.
The optimal pH for sulfate‑based buffers is when pka=pH, that means that optimal pH is 2.
I hope it helps!