Final answer:
Stronger acids within pairs can be predicted by considering factors such as electronegativity and oxidation states. H₂SO₃, H₂SeO₄, H₂SO₄, HBr, and HF are examples of stronger acids within their respective pairs due to such considerations.
Step-by-step explanation:
Predicting the Stronger Acid in Acid Pairs
To determine which acid is stronger within each pair, we consider factors like electronegativity, oxidation state, and the stability of the conjugate base:
- H₂SO₃ or H₂SeO₃: Sulfur is more electronegative than selenium, so H₂SO₃ is typically considered to be the stronger acid.
- H₂SeO₄ or H₂SeO₃: H₂SeO₄ is the stronger acid because it has more oxygens, leading to greater electron-withdrawing effects and consequently a stronger acid.
- HBr or H₂S: HBr is a stronger acid due to bromine's higher electronegativity compared to sulfur.
- H₂SO₄ or H₂SeO₄: H₂SO₄ is the stronger acid because sulfur is more electronegative than selenium.
- HF or HBr: HBr is the stronger acid because bromine is less electronegative than fluorine, making it easier for HBr to donate a proton.
Other comparisons like NH₃ vs. H₂O, or NH₃ vs. PH₃, involve evaluating whether the substance can donate a proton (acid) or accept a proton (base). For instance, H₂O is more acidic compared to NH₃ because it can more readily donate a proton.