AcidBase Theories

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Acid-Base Theories
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Arrhenius Acids Bases

• Early 1900s
• Acids Compound that increases the concentration
  of Hydrogen ions (H) in aqueous solns
• Bases compound that increases the concentration
  of hydroxide ions(OH-) in aqueous solns
• These definitions are correct but not general
  enough and they rely on the use of water as a
  solvent

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Bronsted-Lowry Acids and Bases

• Bronsted-Lowry Acid A molecule or ion that is a
  proton donor
• Ex. HCl(g) ? H(aq) Cl-(aq)
• Bronsted-Lowry Base A molecule or ion that is a
  proton acceptor
• Ex. NH3(aq) ? NH4(aq)
• Bronsted-Lowry acid-base reaction Protons are
  transferred from one reactant (acid) to another
  (base)

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• Monoprotic Acids
• An acid that can donate one proton (Hydrogen ion)
  per molecule
• Ex HCl, HNO3
• Polyprotic Acids
• An acid that can donate more than one proton per
  molecule
• Ex H2SO4, H2CO3
• Diprotic donates 2 protons / molecule
• Triprotic donates 3 protons/molecule

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Lewis Acids/Bases

• Lewis Acid An atom , ion, or molecule that
  accepts an electron pair to form a covalent bond
• Lewis Base An atom, ion, or molecule that
  donates an electron pair to form a covalent bond
• This theory is especially useful in organic
  chemistry acid/base identification