Final answer:
In the pair HNO₃ or HNO₂, HNO₃ is the stronger acid due to its higher oxidation state for nitrogen and more electronegative central atom. In the pair HClO₄ or HClO, HClO₄ is the stronger acid because it has higher electronegativity and a more stable conjugate base.
Step-by-step explanation:
In order to predict which acid is stronger in each pair, we need to look at their molecular structures and determine their strengths based on their chemical properties. a) HNO₃ or HNO₂: Nitric acid (HNO₃) is a stronger acid compared to nitrous acid (HNO₂). This is because nitric acid has a higher oxidation state for nitrogen and a more electronegative central atom, which leads to a stronger attraction for the hydrogen atom and easier release of protons. Nitrous acid, on the other hand, is a weaker acid because it has a lower oxidation state for nitrogen and a less electronegative central atom, resulting in a weaker attraction for the hydrogen atom and less ease of releasing protons.
b) HClO₄ or HClO: Perchloric acid (HClO₄) is a stronger acid compared to hypochlorous acid (HClO). This is because perchloric acid has a higher electronegativity for the central atom and a more stable conjugate base, which allows for easier release of protons. Hypochlorous acid, on the other hand, has a lower electronegativity for the central atom and a less stable conjugate base, resulting in a weaker acid strength and less ease of releasing protons.