THE ELECTROLYSIS OF WATER

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THE ELECTROLYSIS OF WATER

• The unique way in which the hydrogen atoms are
  attached to the oxygen atom causes the hydrogen
  side of the molecule to have a positive charge
  and the oxygen side to have a negative charge.

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• The Hydrogen atoms are attracted to the
• - charged terminal, and are pulled off the
• H2O molecule, filling the right tube in this
  diagram with Hydrogen gas.

3

• The - Oxygen atoms are attracted to the
• charged terminal, and are pulled from the
• H2O molecule, filling the left tube in this
  diagram with Oxygen gas.

4

• H2O consists of 2 H atoms and 1 O atom so twice
  as much Hydrogen gas will be produced

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2H2O ? 2H2 O2

• Faraday's 1st Law of Electrolysis - The mass of a
  substance altered at an electrode during
  electrolysis is directly proportional to the
  quantity of electricity transferred at that
  electrode. Quantity of electricity refers to the
  quantity of electrical charge, typically measured
  in coulomb.
• IN OTHER WORDS Stronger battery more
  electricity more gas produced (and faster, too)

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Faradays laws continued

• Faraday's 2nd Law of Electrolysis - For a given
  quantity of electricity (electric charge), the
  mass of an elemental material altered at an
  electrode is directly proportional to the
  element's equivalent weight.
• IN OTHER WORDS Since there are twice as many
  Hydrogen atoms as Oxygen atoms in 2H2O, TWICE as
  much HYDROGEN gas will be produced as Oxygen gas

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• IS THIS A PHYSICAL OR A CHEMICAL CHANGE?
• WHAT EVIDENCE SUGGESTS THIS?

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• 2H2O ? 2H2 O2
• WHAT DOES THE FORMULA ABOVE SUGGEST ABOUT THE
  REACTION?
• HOW CAN WE BE SURE?

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• HOW DO WE IDENTIFY THE GAS????

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FLAME AND GLOWING CINDER TESTS
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• HYDROGEN GAS CAN EXPLODE WITH A POP, AND CAN
  EMIT A BRIEF FLASH OF LIGHT.
• SHOULD WE TRY IT?????

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• Are you SURE?????
• Its REALLY DANGEROUS!!!!
• Its VERY LOUD AND SCARY!!!!
• ARE YOU SURE???