Calcium Ion-Selective Electrode
Recommended for College and High School. Interface and software sold separately.
The Calcium Ion-Selective Electrode (ISE) can be used to measure the concentration of Calcium (Ca2+) in aqueous samples.
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: 0.20 to 40,000 mg/L or ppm (5 × 10-6 M to 1.0 M)
Resolution (LabQuest 2, LabQuest, LabQuest Mini, Go!Link, LabPro):
- % of reading: 1.4%
- Low scale reading: 0.20 ±0.0028
- High scale reading: 40,000 ±560 mg/L
- pH Range: 3 to 10
- Interfering Ions: Pb2+, Hg2+, Sr2+, Cu2+, Ni2+
- Electrode Resistance: 1 to 4 MΩ
- Electrode Slope (log voltage vs. concentration): +28 mV/decade
- Reproducibility: ± 5% of reading
- Temperature range (can be placed in): 0 to 50°C (no temperature compensation)
- Minimum immersion: 1 inch
- Electrode Length: 155 mm
- Body Diameter: 12 mm
- Cap Diameter: 16 mm
- Cable Length: 100 cm
Download the user manual for full specifications
Experiments and Lab Ideas
Water Quality with Vernier (1)
Includes student instructions, teacher tips, safety information, and sample data.Go to Book Page
Lab Ideas and Innovative Uses
- 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
The Calcium Ion-Selective Electrode requires a compatible interface and software to collect data. Interface and software sold separately. Getting started with probeware »
The Calcium Ion-Selective Electrode is compatible with these interfaces:
Educational use only: Vernier products are designed for educational use. They are not appropriate for industrial, medical, or commercial applications. Product usage disclaimer »