1. What is Water Resistivity?

Water resistivity (ρ) is a measure of how strongly water resists electric current flow. It depends on the concentration of dissolved ions in the water, with purer water having higher resistivity.

2. How Does the Calculator Work?

The calculator uses the resistivity formula:

Where:

• \( \rho \) — Resistivity (Ω·m)
• \( R \) — Electrical resistance (Ω)
• \( A \) — Cross-sectional area of water sample (m²)
• \( L \) — Length between electrodes (m)

Explanation: The formula calculates the intrinsic property of water to resist electrical current, independent of the sample dimensions.

3. Importance of Water Resistivity Measurement

Details: Water resistivity is crucial for assessing water purity in laboratories, pharmaceutical manufacturing, semiconductor production, and power generation. Higher resistivity indicates purer water with fewer dissolved ions.

4. Using the Calculator

Tips: Enter resistance in ohms (Ω), cross-sectional area in square meters (m²), and length in meters (m). All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the typical resistivity range for different types of water?
A: Distilled water: 0.1-1 MΩ·m, Deionized water: 1-18 MΩ·m, Ultrapure water: 18.2 MΩ·m, Tap water: 10-100 Ω·m.

Q2: Why does temperature affect water resistivity?
A: Temperature affects ion mobility and dissociation. Resistivity decreases as temperature increases due to increased ionic activity.

Q3: How is resistivity different from conductivity?
A: Resistivity is the reciprocal of conductivity. High resistivity means low conductivity and vice versa.

Q4: What factors affect water resistivity measurements?
A: Temperature, dissolved ions, carbon dioxide absorption, and electrode polarization can all affect measurements.

Q5: Why is high resistivity important in industrial applications?
A: High resistivity water prevents corrosion, scaling, and contamination in processes like semiconductor manufacturing and power plant operations.