Presentation OnElectric Conductivity (EC)

Prepared by Md. Aminur Rahman

Senior Chemist .DPHE Zonal Lab.,

Khulna.

Pocket Pal TM

Conductivity Tester

Presentation OnElectric Conductivity (EC)

Conductivity is a measure of the ability of an aqueous solution to carry an electric current. This ability depends on -•The total concentration of ions (cations & anions )• Their mobility, Valance and •Temperature

Unit : -µS/cm, -s/m, - mho (ohm-1) Bangladesh standard value: Nil

Why does we measure it ?• It is one the indicator of water purity.• We can get idea about TDS, Salinity from it.• One can guess whether the sample water

contains sewage ,Industrial drainage and sea water.

• We can guess the degree of mineralization.

Measuring procedure of Conductivity Tester

• Take about 25/30 ml sample in a beaker.• On the EC meter by pressing ON/OFF button &

remove the protective Cap• Immerse the bottom of the tester into the

sample.• Using the tester gently stir the sample & wait

some times for reading.Note: Its measuring range 10-1990 µS/cm at 0-50˚C

temperature. Verify its accuracy by measuring known calibration standard.

Maintenance• Use distilled water to wash the bottom of the

tester .• Wipe it with tissue paper after using & Replace

the cap.• Always off the switch after using.• Maintain or Improve performance by periodically

rinsing the stainless steel electrode in Isopropyl alcohol.

Typical range of conductivities of various types of natural waters

Type of water EC (µS/cm)Rain water 10-100

Stream and river water 30-2000

Shallow ground water 100-5000

Deep ground water 300-5000

Saline ground water and brines 5000-300000

Conclusion

To get accurate EC result, measure immediately after sample collection.

Thank you for

your all kind attention.

Presentation on pH

Present By

Md. Aminur RahmanSenior Chemist

DPHE, Zonal Lab. Khulna.

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pHWhat is pH ?• pH is the Negative logarithm of the

concentration of hydrogen ion in a solution. • pH= -log [H+]. • If pH value < 7, sample is Acidic. pH value = 7, sample is neutral. pH value >7,sample is alkaline.• pH depends on temperature. Pocket pH meter

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Measuring pH By HACH Sension156

Operating flow diagram • Connect pH probe to the back

of the meter• Press EXIT button to “on” the

meter.• Press pH button to select pH

mode.• Press pH button to display “

pH & Temp.” mode. • Put the probe into the sample.• Press READ / Enter button

pH probe

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Operating flow diagram

• “Beep” - sound to stabilize the reading

• Appear pH reading.

Multimeter

Thank you for

your all kind attention.