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HARDNESS of WATER
An EDTA Titration
There is a ........  TUTORIAL

More about.... HARD WATER

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In this experiment you will determine the hardness of water.
This involves the following series of steps:

  1. Prepare the STANDARD
    • Accurately weigh out a sample of pure calcium carbonate, CaCO3
    • Dissolve this with HCl
    • Quantitatively transfer this to a 100 mL volumetric flask, dilute to volume and mix thoroughly.
  2. STANDARDIZE the EDTA solution.
    • Pipet out a 10.00 mL aliquot of the STANDARD
    • Titrate to the eriochromschwartz-T end point.
    • Do the standardization in triplicate
      precision should be well within 1% (.1 mL)
  3. TITRATE the UNKNOWN
    • Titrate a 20 mL aliquot of UNKNOWN
    • Do this in duplicate again to 0.05 - 0.10 mL precision
  4. TITRATE your water from HOME.
  5. Enter EXPERIMENTAL DATA into COMPUTER
  6. Do CALCULATIONS
  7. Enter calculations into COMPUTER
  8. Get your GRADE.
For further information and details, look up..........................EQUATIONS
There is a .... WARNING and Experimental ERROR ANALYSIS!
This deals with the Experimental Errors which can lower the accuracy of your experimentally determined Calcium concentration.
Experimental errors do not involve your calculated values.
...
Some sources of experimental errors
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weighing transfering pipeting titrating

R.W. Kluiber 1/28/2000