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Calcium Ion-Selective Electrode

The Calcium Ion-Selective Electrode (ISE) can be used to measure the concentration of Calcium (Ca2+) in aqueous samples.

SKU: CA-BTA Categories: ,


Data from the Calcium ISE can give a good indication of hardness of water (as Ca2+). The concentration of Calcium is also used as an endpoint indicator in EDTA-Ca/Mg hardwater titrations.

The Calcium ISE has a combination-style, non-refillable, gel-filled electrode. Like all other PVC ISE membranes, the membrane on the ISE has a limited life expectancy. However, the replaceable module of ISE allows you to simply discard the used membrane module, and replace it with a new one.

Note: We recommend that you do not purchase ISE replacement modules too far in advance of their expected time of use as degradation occurs while they are stored on the shelf.

Important: Ion-Selective Electrodes require good chemical technique and careful calibration to obtain accurate results; they are not recommended for middle school or elementary students.

Range (concentration): 1 to 40,000 mg/L (or ppm)
Reproducibility (precision): ± 10% of full scale (calibrated 10 to 1000 mg)
Interfering Ions: Pb2+, Hg2+, Si2+, Fe2+, Cu2+, Ni2+, NH3, Na+, Tris+, Li+, K+, Ba2+, Zn2+, Mg2+
pH Range (concentration): 2–8 (no temperature compensation)
Electrode Slope: +26 mV/decade at 25°C
Electrode Resistance: 100 MΩ
Immersion: 2.8 cm (1.1 in)
Electrode length 155 mm
Body diameter: 12 mm
Cap diameter: 16 mm
Cable length: 100 cm

Vernier Calcium Ion-Selective Electrode
30 mL bottle of Calcium Low Standard (10 mg/L)
30 mL bottle of Calcium High Standard (1000 mg/L)
Short-term ISE soaking bottle
User manual

Electrode Support (ESUP)

Calcium Replacement Module (CA-MOD)
Electrode Storage Bottles (BTL-ES)
Standard Ca ISE Solution ()

User Manual:
Warranty: 5-year limited warranty (1 year on module, none on consumables)