Electrolytes

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Electrolytes
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• Electricity The flow of charged particles (such
  as electrons or ions) resulting in the transfer
  of energy.

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• Electrical Conductor A substance (or mixture)
  that allows electric current to pass through it.
• To be a conductor, a species must have charged
  particles that are able to move around.

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Pure water does not conduct an electric
currentAlthough the molecules are free to move
around, they are not charged.
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Ionic solids do not conduct electricity.Although
they have charged particles, the particles are
not free to move around.
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Ionic Solutions conduct a Current
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• Electrolyte a substance that conducts
  electricity when in solution due to the movement
  of electrons.

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Strong electrolyte

• A strong electrolyte is a substance that breaks
  up almost completely into ions when dissolved in
  water.
• The resulting solution is an excellent conductor
  of electricity due to the large number of charged
  particles.

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Strong electrolyte
Strong electrolytes exhibit nearly 100
dissociation.
Before dissolving 1000 0 0
In solution 0 1000
1000
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Strong electrolyte

• Substances known to be strong electrolytes
• Soluble ionic compounds
• Strong acids
• - HClO4, HClO3, HCl, HBr, HI, HNO3, H2SO4
• Strong bases
• - LiOH, NaOH, KOH, CsOH, Ca(OH)2, Sr(OH)2,
  Ba(OH)2

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Weak electrolyte

• A weak electrolyte is a substance that has only a
  few particles break up into separate ions when
  dissolved in water.
• The resulting solution can conduct electricity
  but not very well.

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Weak electrolyte
Weak electrolytes exhibit little dissociation.
Before dissolving 1000 0 0
In solution 980 20
20
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Weak electrolyte

• Substances known to be weak electrolytes
• Insoluble ionic compounds
• Weak acids
• Weak bases

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Nonelectrolyte

• A nonelectrolyte is a substance that doesnt
  break up into any ions when dissolved in water.
• The resulting solution is unable to conduct
  electricity due to the lack of any charged
  particles.

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Nonelectrolyte
Nonelectrolytes exhibit no ionization.
C12H22O11 (s) ? C12H22O11
(aq) Before dissolving 1000 0 In
solution 0 1000
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Nonelectrolyte

• Substances known to be nonelectrolytes
• Molecular compounds
• - The most common examples of molecular
  compounds that do dissolve in water but dont
  break up into ions are sugars and alcohols.
• - When sugars and alcohols dissolve, the
  molecules separate from each other, but they
  dont break up into smaller parts.
• - The particles in solution are neutral
  molecules, so the solution cannot conduct
  electricity.

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Net-Ionic Equations

• The purpose of ionic equations is to show species
  exactly how they truly exist.
• When we write ionic equations, we need to
  represent dissolved species either as ions (if
  the substance gets ionized extensively) or as
  molecules (if the substance only gets ionized to
  a small extent, or not at all).
• Strong electrolytes exist as ions in solution.
• Weak electrolytes exist primarily as molecules in
  solution.
• Nonelectrolytes exist completely as molecules in
  solution.

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Net-Ionic Equations

• For example, lets write CIEs and NIEs for the
  following reactions.
• Solutions of magnesium nitrate and sodium
  carbonate are mixed.
• Solutions of hydrobromic acid and calcium
  hydroxide are mixed.
• Solutions of phosphoric acid and potassium
  hydroxide are mixed.