Skip to main content
[ "stage:draft", "article:topic", "acid", "base", "Ionic Bonding", "showtoc:no", "hydroxides", "Oxides", "Metallic Oxides", "Covalent Hydrides", "Ionic Hydrides", "Semimetal Oxides", "Non-Metal Oxides" ]
Chemistry LibreTexts

Acid-Base Character of Oxides and Hydroxides

  • Page ID
    68247
  • From left to right on the periodic table, acid-base character of oxides and hydroxides go from basic to acidic.

    • Increasing charge on an anion increases the production of basic solutions.
    • As electronegativity increase, production of ionic cations increases because elements are more able to adopt a cation.
    • As ionization energy increases, the acidic nature increases.

    Metallic Oxides:

    - Ionic Bonding: no distribution of electron wave function

    - Ionic oxides are usually basic (element act as a base when reacting with H2O)

    Na2O(s) + H2O(l) --> 2NaOH(aq) --> 2Na+(aq) + 2OH-(aq)


    B. Oxide B. Hydroxide

    Semimetal Oxides:

    - Semimetal are amphoteric (elements acts as an acid and/or base when reacting depending on pH of solution)

    Al2O3 --> Al(OH)3 --(3H+)--> [Al(H2O)6]^(3+) (aq)


    --(OH-)--> [Al(OH)4]-(aq)

    Non-Metal Oxides

    - Covalent Bonding: almost complete distribution of electron wave function

    - Covalent oxides are usually acidic (elements act as an acid when reacts with H2O)

    SO3 + H2O(l) -> H2SO4(aq) -> H+ + HSO4-


    A. Oxide A Hydroxide

    Ionic Hydrides

    0 6 a

    Types of Hydrides

    - Ionic Bonding: no distribution of electron wave function

    - Bronsted Basic because they will react with proton

    - Lewis Basic because they can be ligands

    CaH2 + 2H2O -> 2H2 + Ca(OH)2


    H- H+ H2


    -In this case, CaH2 is basic because it reacts with water (an acid in this case) to form many hydrides by reducing a proton.

    Covalent Hydrides

    - Covalent Bonding: almost complete distribution of electron wave function

    HF + H2O -> F- + H3O+ ....can also be written as HF(aq) <--> H+(aq) + F-(aq)

    H+ H+ H+

    - HF is a weak acid that is bronsted acid because it will loose a proton. Therefore, HF is the weak acid, where the water acts as a silent water, and F- is the weak conjugate base.

    0 6 b