Knight:pH meter/Calibration: Difference between revisions

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*pH standard solution 7.0
*pH standard solution 7.0
*pH standard solution 10.0
*pH standard solution 10.0
*3 20mL beakers
*1 beaker to collect washes
*1 beaker to collect washes
*Squirt bottle with distilled water
*Squirt bottle with distilled water
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#Press the '''CAL''' key.
#Press the '''CAL''' key.
#Press the '''CLEAR''' key twice to remove existing calibration.
#Press the '''CLEAR''' key twice to remove existing calibration.
#Pour 1 inch of standard pH buffer 4 into small beaker.
#Immerse the tip of the electrode into pH buffer 4 bottle.
#Immerse the tip of the electrode into beaker.
#Press the '''READ''' key.
#Press the '''READ''' key.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 4.00.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 4.00.
#Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
#Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
#Touch electrode gently with Kimwipe to remove excess fluid.
#Touch electrode gently with Kimwipe to remove excess fluid.
#Pour 1 inch of standard pH buffer 7 into small beaker.
#Immerse the tip of the electrode into pH buffer 7 bottle.
#Immerse the tip of the electrode into beaker.
#Press the '''READ''' key.
#Press the '''READ''' key.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 7.00.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 7.00.
#Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
#Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
#Touch electrode gently with Kimwipe to remove excess fluid.
#Touch electrode gently with Kimwipe to remove excess fluid.
#Pour 1 inch of standard pH buffer 10 into small beaker.
#Immerse the tip of the electrode into pH buffer 10 bottle.
#Immerse the tip of the electrode into beaker.
#Press the '''READ''' key.
#Press the '''READ''' key.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 10.01.
#Wait until the Auto-Eye stops flashing.  The pH meter should read 10.01.

Revision as of 14:43, 8 January 2007

Overview

Some quick notes on how to calibrate our pH meter.

Materials

  • pH standard solution 4.0
  • pH standard solution 7.0
  • pH standard solution 10.0
  • 1 beaker to collect washes
  • Squirt bottle with distilled water
  • Kimwipes

Procedure

  1. Raise the electrode out of the storage buffer.
  2. Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
    • Do not rinse the electrode into the soak beaker.
  3. Touch electrode gently with Kimwipe to remove excess fluid.
  4. Press the CAL key.
  5. Press the CLEAR key twice to remove existing calibration.
  6. Immerse the tip of the electrode into pH buffer 4 bottle.
  7. Press the READ key.
  8. Wait until the Auto-Eye stops flashing. The pH meter should read 4.00.
  9. Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
  10. Touch electrode gently with Kimwipe to remove excess fluid.
  11. Immerse the tip of the electrode into pH buffer 7 bottle.
  12. Press the READ key.
  13. Wait until the Auto-Eye stops flashing. The pH meter should read 7.00.
  14. Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
  15. Touch electrode gently with Kimwipe to remove excess fluid.
  16. Immerse the tip of the electrode into pH buffer 10 bottle.
  17. Press the READ key.
  18. Wait until the Auto-Eye stops flashing. The pH meter should read 10.01.
  19. Press the CAL or EXIT key to exit the calibration mode.
  20. Rinse with distilled water from a squirt bottle over a beaker used to collect washes.
  21. Touch electrode gently with Kimwipe to remove excess fluid.

The pH meter is calibrated for measuring the pH of most buffers and solutions. For more exact measurements or to pH solutions with more extreme pH, you may need additional/alternate calibration buffers.

Notes

  • The electrodes of pH meters are both fragile and expensive. Be careful when immersing it to not hit it against the beaker.

References

  1. [Manual]
  2. ISBN:0879697083 [AtTheBench]

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