User manual HANNA INSTRUMENTS HI 4014

[. . . ] HI 4114 POTASSIUM COMBINATION HI 4000-50 SENSOR HANDLE Instruction Manual HI 4014 HI 4114 Potassium Ion Selective Electrode Half-cell Combination 1 Potassium HI 4014 Potassium half-cell Potassium HI 4114 Potassium combination electrode I. Introduction Hanna HI 4014 and HI4114 are ion selective electrodes designed for the measurement of potassium ions in aqueous solutions. They utilize a replaceable sensing module that contains an organic polymer membrane that is sensitive to potassium. HI 4014 is a half-cell electrode that requires a separate reference. [. . . ] 4) Prepare reference electrode by filling outer electrolyte reservoir with fill solution HI 7076. 5) Place sensor (and reference) electrodes into electrode holder and connect cable connectors to meter. 6) Soak the potassium membrane in a potassium containing standard for a hour before calibration. HI 4114 The Hanna HI 4114 is shipped dissembled. Unwrap Parafilm® seal found over ceramic junction on inner stem and discard. This is only used for shipping and long term storage. Open the glass vial (HI 4114-51) and remove the potassium sensing cone. Do not touch the sensing membrane with the "H" hole pattern on it. Ensure o-ring is installed on module before screwing the cone into the inner stem finger tight. Rinse inner stem with deionized water making certain to wet o-ring found on the inner stem. Reassemble electrode by gently pushing the inner assembly into the outer body, sliding spring down cable, and screwing cap into place. Remove fill hole cover and o-ring on fill hole spout. Using the dropper pipette provided, add a few drops HI 7076 fill solution to the electrode, wetting the oring and rinsing out the fill solution chamber. 9 7. Holding the body of the electrode gently press the upper cap with your thumb. This permits the fill solution to drain out of the body. Release the cap and verify electrode returns to its original position. (You may need to gently assist for this to occur). 9. Tighten the electrode cap onto the body and fill electrode body until fill solution volume is just below fill hole. Position electrode in a Hanna HI 76404 electrode holder (or equivalent) and connect BNC connector to meter. · · · Quick Check of Electrode Slope Connect electrode(s) to pH/mV/ISE meter. Place 100 mL of deionized water into a beaker with stir bar. · Place reference and measuring half-cell or combination electrode into prepared sample. [. . . ] A pH/mV meter in mV mode and semi log graph paper may also be used. Two or more freshly prepared standards that are in the measurement range of the unknowns (with ISA added), are measured in mV mode on the meter. These values are plotted on semi-log paper and the points are connected to form a straight-line curve. When samples are measured, their mV values are converted to concentration by following the mV to the concentration axis on the semi-log plot. [. . . ]