Electrolytes

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Electrolytes

• Pure water does not
• conduct electricity. It is the
• substances dissolved that
• permit the passage of current.
• These substances are called
• electrolytes

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Electrolyte

• An electrolyte is a substance that when dissolved
  in water permits the passage of an electric
  current

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Electric conductibility

• The electric conductibility of a solution is its
  capacity to allow the passage of an electric
  current

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Different water/Different electrolytes

• Ocean water, river water and lake water all have
  electrolytes with different concentrations.
• Many living organisms need electrolytes to
  survive.

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Electric dissociation

• Electric dissociation is the separation of a
  dissolved substance into two ions of opposing
  charges

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Strength of an electrolyte

• The strength of an electrolyte depends on the
  rate of dissociation. The higher the rate the
  stronger the electrolyte
• (the more ions forming the stronger the
  electrolyte)
• NaCl very good electrolyte (high dissociation
  rate)
• HF weak electrolyte (low dissociation rate)

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Types of electrolytes

• Acids, bases and salts are the 3 important types
  of electrolytes ,

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Acids

• An acid is a substance that release H ions in an
  aqueous solution
• (Aqueous solution water as its solvent)

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Bases

• A base is a substance that releases OH- ions in
  an aqueous solution

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Salts

• A salt is a substance that provides a bond
  between a metal ion () and a non metal ion (-)

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pH

• The pH is a property that permits to distinguish
  a solution from acidic, basic or neutral.
• We can use an indicator to determine the pH

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pH scale

• The pH scale goes from 0 to 14. It determines the
  degree of acidity of a substance
• pH lt 7 ? acid
• pH gt 7 ?base
• pH 7 ? neutral
• The pH scale is logarithmic meaning that the
  difference of 1 unit between two substances is in
  reality 10 times greater
• i.e. A pH of 3 is 10 times more acidic than a pH
  of 4

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