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13

XII. 

XII. 

XII. 

XII. 

XII.  Other Measurement T

Other Measurement T

Other Measurement T

Other Measurement T

Other Measurement Techniques

echniques

echniques

echniques

echniques

Known Addition  (for Cl

-

)

An unknown concentration can be determined by adding a
known amount (volume and concentration) of measured
ion to a known volume of the sample. This technique is
called Known Addition.   The method can use an ideal
sensor slope, but actual determined slopes at the tempera-
ture of measurement should be used if known.  This method
is preprogrammed in the Hanna HI 4222 pH/ISE/mV meter,
which simplifies the method greatly.
Example: Chloride ion determination with known addition.
1. A 50 mL sample of unknown (Vsample) is placed in

a clean plastic beaker with a chloride sensor. Add 2
mL of acetate pH buffer or HI 4000-00 ISA (V

ISA)

 OR if

chloride l electrode interferences are known to exist,
add 50 mL oxidizing reagent (V

ISA

). Mix well. and

record the stable mV value. (mV 1)

2. 5 mL (Vstd) of 10

-3

M (Cstd) standard is added to the

beaker and the mV value decreases.  The unknown
chloride concentration in the original sample
(Csample) can then be determined by the following
equation.

3. The procedure can be repeated with a second stan-

dard addition to verify slope and operation of the
method.

 C

sample 

=

(

V

T

)10

E/S 

- (

V

S

)

C

standard

V

standard

V

sample

V

S

(

V

sample

+

V

standard

+

V

ISA

)= 

V

T

(

V

sample

+

V

ISA

)= 

V

S

Содержание HI 4107

Страница 1: ...HI 4007 HI 4007 HI 4007 HI 4007 HI 4007 HI 4107 HI 4107 HI 4107 HI 4107 HI 4107 Chloride Ion Selective Electrode Instruction Manual CHLORIDE HI 4007 HI 410 COMBINATION 7 CHLORIDE Half cell Combinatio...

Страница 2: ...utions The HI 4007 is a solid state half cell sensor that requires a separate reference The HI 4107 is a combination ion selective electrode II II II II II Specifications Specifications Specifications...

Страница 3: ...asareferenceelectrode incorporated in its design The silver chloride pellet is prac tically insoluble in the test solutions being measured and producesapotentialchangeduetochangesinthesample s ion act...

Страница 4: ...4107 Design elements of the HI 4007 and HI 4107 Design elements of the HI 4007 and HI 4107 electrodes electrodes electrodes electrodes electrodes CHLORIDE HI 4007 Cap Sensing Membrane Sensor Handle U...

Страница 5: ...lutions Required Solutions Required for Chloride Measurements for Chloride Measurements for Chloride Measurements for Chloride Measurements for Chloride Measurements Select appropriate Hanna Instrumen...

Страница 6: ...libration standards and sample solutions should have the same ionic strength ISA acetate buffer or oxidizing reagent should be added to both samples and standards in the same ratio Calibration standar...

Страница 7: ...ing normal use fill solution will slowly drain out ofthetaperedconejunctionatthelowerportionofthe electrode Excessiveloss 4cmdropwithin24hours isnotnormal Ifthisoccursverifycapistightenedand the inter...

Страница 8: ...m seal found over ceramic junction on inner stem and discard This is only used for ship ping and long term storage 2 Rinseinnerstemwithdeionizedwatermakingcertain to wet the o ring found on the inner...

Страница 9: ...verify elec trodereturnstoitsoriginalposition Youmayneedto gently assist for this to occur 7 Tighten the electrode cap onto the body and fill elec trode body until fill solution volume is just below f...

Страница 10: ...action Corrective action Corrective action Corrective action Corrective action Verify protective cap has been removed HI 4007 Verify plastic film has been removed from inner stem HI4107 Verify electr...

Страница 11: ...he meter is calibrated with two or more freshly made stan dards that are in the linear measurement range of the unknowns Morecalibrationstandardsarerequiredinnon linear regions Unknowns are read direc...

Страница 12: ...ements using the oxidizing reagent must be made 10 minutes after mixing and not permitted react longer 3 Follow sectionVII GeneralGuidelinestooptimizetest set up 4 Duringcalibrationitisbesttostartwith...

Страница 13: ...mplifies the method greatly Example Chloride ion determination with known addition 1 A 50 mL sample of unknown Vsample is placed in a clean plastic beaker with a chloride sensor Add 2 mLofacetatepHbuf...

Страница 14: ...r See Section VI Titration Titration Titration Titration Titration XIV S XIV S XIV S XIV S XIV Storage and Care of the HI 4007 and torage and Care of the HI 4007 and torage and Care of the HI 4007 and...

Страница 15: ...s Conversion tables Conversion tables Conversion tables Conversion tables For Cl For Cl For Cl For Cl For Cl Multiply by Multiply by Multiply by Multiply by Multiply by Moles L M to ppm mg L 3 500x104...

Страница 16: ...6 monthsfromdateofpurchasewhenusedfortheirintended purpose and maintained according to instructions If they failtoworkwhenfirstusedcontactyourdealerimmediately Damageduetoaccidents misuse misapplicat...

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