Hanna Instruments 

The HA-HI4007 chloride ion selective electrode is a potentiometric half-cell sensor housed within an epoxy body. The internal elements are isolated from the sample by a compressed silver chloride sensing membrane. This solid state sensor requires a separate reference electrode to complete the measurement system.

Hanna’s solid-state half-cell ISEs are designed for use with the HA-HI5315 reference half-cell. The reference half-cell features a cone style junction. The skirted cone geometry of the reference forms the liquid junction with the test solution at the tip of the junction cone, producing a highly stable reference potential and consistent flow rates of electrolyte into the solution. A simple press of the top portion of the ISE makes it easy to empty the electrolyte fill solution and replace when necessary

For the HA-HI4007 to measure chloride accurately, it is important that the ionic strength of the standards and sample be adjusted to a high and constant value with the halide ionic strength adjuster (ISA) solution. The halide ISA ensures that the activity coefficient is constant so the concentration of free chloride ions can be measured. Measuring all solutions with a constant ionic strength reduces the margin of error between measurements. The HA-HI4007 chloride solid state ISE can measure from 50µM (1.8 mg/L) to 1M (35,500 mg/L).