Acid Base and redox

Arrhenius

• Acid → produces H+ ion in water

• Base → Produces OH- in water

Bronstead lowry

• Acid → proton donor

• Base → proton acceptor

Acid base reaction

• Weak acid doesnt fully ionize in solution

  • doesnt turn into OH or H3O, where as strong acids do

• Titrations

  • When a substance being analyzed contains an acid

    • we use indicator to see how much of an acid or base needed to change PH

Examples

$$\begin{array}{r}0.350\frac{mol}{L}NaOH\ast 0.0250LNaOH\ast \frac{1molHCL}{1molNaOH}\ast \frac{1}{0.08750LHCl}\end{array}$$

Redox

• Oxidation and reduction reactions

  • Its a reaction when one or more electrons are transferred

• Definitions

  • Oxidation

    • loss of electrons

  • Reduction

    • a gain of electrons

• Oxidation states

  • Concept of oxidation states (or oxidation numbers) a way to keep track of electrons

  • simple rules

    • 1.

      • the oxidation state of an atom in an element is 0

    • 2.

      • the oxidation state of a monoatomic ion is the same as its charge

    • 3.

      • in its covalent compounds with nonmetals, hydrogen is assigned an oxidation state of +1

    • 4.

      • in its compounds, oxygen is assgined an oxidation state of -2

    • 5.

      • in its compounds fluorine is always assigned an oxidation state of -1
        • in its compounds, the other halogens are usually -1 except in combination with oxygen or other halogens. in its compounds, nitrogen is usually assigned an oxidation state of -3

• Balancing: half reaction

  • Fro redox reactions that occur in aquous solutions it is often useful to seprate the reaction

  • Example

    • $Cr{I}_3+C{l}_2$→$Cr{O}_4^{2-}+I{O}_4^{-}+C{l}^{-}$
      • we know that each halogen is -1 when no flourine
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