Since Avogadro and Loschmidt we call 6 . 1023 atoms or molecules one mole of a substance. One mole = 602213673600000000000000 particles.

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Titration counts One mole can you imagine?

• Since Avogadro and Loschmidt we call 6 . 1023
  atoms or molecules one mole of a substance. One
  mole 602213673600000000000000 particles.
• Can you imagine what that means?
• - One mole of marbles spreaded on the globe
  would form a layer of 3 km thickness
• - Assuming that a computer could count 10
  Million molecules in one second, it would need
  2 trillions of years to count one mole of them
• - One mole of dollar 100 Euro-bills stacked on
  top of each other would fill the distance
  Sun-Pluto 7,5 million times

http//www.unit5.org/christjs/Stoichiometry/The20
Mole20Concept.ppt262,6,Careers in Chemistry
Philosopher
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Titration is what counts More images to
represent one mole

• Assuming that each human being has 60 trillion
  body cells (6.0 x 1013) and the Earth's
  population is 6 billion (6 x 109), the total
  number of living human body cells on the Earth at
  the present time is 3.6 x 1023or a little over
  half of a mole.
• If one mole of pennies were divided up among the
  Earth's population, each person would receive 1 x
  1014 pennies.  Personal spending at the rate of
  one million dollars a day would use up each
  persons wealth in about three thousand years. 
  Life would not be comfortable because the surface
  of the Earth would be covered in copper coins to
  a depth of at least 400 meters.
• http//lvstem.cse.lehigh.edu/teams/freedom/The20
  Mole-intro-actvity-lesson20plan.doc
• Each screw in a package of screws and nuts
  corresponds to one nut an analogy for the
  reaction of monoprotic acid with e.g.
  NaOH-solution

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Titration is what counts

• When you weigh, you count molecules 60 g of
  acetic acid contain one mole of molecules
• When you now dilute or dissolve the acid, you
  have a defined number of molecules in a given
  volume
• When you now titrate this solution to check the
  molarity, with e.g. NaOH-solution, you react the
  number of acetic acid molecules contained in the
  volume of solution with the base. If the
  hydroxide ion content of the NaOH-solution is
  known, you can calculate the concentration of the
  acid from the volume of base needed to reach the
  equivalence point.
• Titration is a rapid, inexpensive and highly
  precise (and accurate) method for the
  determination of analytes and it does not need
  calibration.

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Experiment

• Titration of household vinegar to measure the
  acetic acid content with sodium hydroxide
  solution
• Phenolphthalein is used as an indicator to mark
  the equivalence point
• The volume of hydroxide solution is used to
  calculate the acid concentration in the vinegar

http//www.dkimages.com/discover/previews/890/2505
3821.JPG
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• The equivalence point of the titration of
  vinegar with NaOH lies in the alkaline region,
  because the resulting salt sodium acetate is the
  salt of a weak acid and a strong base hence it
  shows an alkaline reaction (pink colour of the
  solution containing phenolphtaleine as an
  indicator)
• one nut for each screw

phenolphthalein is colourless in the acidic and
pink in the basic region