Final answer:
The formula for the oxyacid derived from the oxyanion SO₄²⁻ is H₂SO₄, which is sulfuric acid. For oxyanions ending in -ite, the formula for the oxyacid is formed by using the base name of the oxyanion followed by -ous and adding the suffix -ic.
Step-by-step explanation:
The oxyacid derived from the oxyanion SO42- is H2SO4, which is sulfuric acid. The naming of oxyacids depends on whether the oxyanion ends with -ite or -ate. For oxyanions ending in -ite, the formula for the oxyacid is formed by using the base name of the oxyanion followed by -ous and adding the suffix -ic. In the case of SO42-, the base name is sulfite, so the formula for the oxyacid is sulfurous acid (H2SO3). However, for oxyanions ending in -ate, the formula for the oxyacid is formed by using the root of the anion followed by the suffix -ic, without using a prefix.