Explain why acid strength increases in the order HIO < HBrO < HClO.

Name: Chemistry
Author: McMurry
ISBN: 9781292336145

검증된 단계별 안내

Step 1: Understand that acid strength is influenced by the stability of the conjugate base formed after the acid donates a proton (H+). A more stable conjugate base corresponds to a stronger acid.

Step 2: Recognize that the stability of the conjugate base is affected by the electronegativity of the central atom. More electronegative atoms can better stabilize the negative charge on the conjugate base.

Step 3: Compare the electronegativities of the central atoms: Iodine (I), Bromine (Br), and Chlorine (Cl). Chlorine is the most electronegative, followed by Bromine, and then Iodine.

Step 4: Relate the electronegativity to acid strength: Since Cl is more electronegative than Br and I, the conjugate base ClO- is more stable than BrO- and IO-, making HClO the strongest acid.

Step 5: Conclude that the order of increasing acid strength is HIO < HBrO < HClO due to the increasing electronegativity of the central atom, which stabilizes the conjugate base more effectively.

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Acid Strength

Acid strength refers to the ability of an acid to donate protons (H+) in a solution. Stronger acids dissociate more completely in water, leading to a higher concentration of H+ ions. The strength of an acid is influenced by the stability of its conjugate base; a more stable conjugate base corresponds to a stronger acid.

Conjugate Base Stability

The stability of a conjugate base is crucial in determining acid strength. When an acid donates a proton, the remaining species is the conjugate base. Factors such as electronegativity and the size of the atom to which the negative charge is assigned affect this stability. A more stable conjugate base results in a stronger acid.

Electronegativity and Bond Strength

Electronegativity is the tendency of an atom to attract electrons. In oxyacids like HIO, HBrO, and HClO, the electronegativity of the central atom (I, Br, Cl) affects the bond strength between the hydrogen and the central atom. As electronegativity increases, the bond becomes weaker, making it easier for the acid to release H+, thus increasing acid strength.