Potentiometry — Definition, Formula, Properties & Uses | AllChemicals | AllChemicals

Q: What is the formula for Potentiometry?

The formula or notation for Potentiometry is: log [ion] ∝ E

Formula / Notation	log [ion] ∝ E
Also Known As	Potentiometric analysis, potentiometry, pH measurement (type), ion-selective electrode measurement

What is Potentiometry?

An electroanalytical technique that measures the potential (voltage) of an electrochemical cell to determine the concentration of a species in solution. The pH meter uses potentiometry with a glass electrode. Ion-selective electrodes extend potentiometry to many other analytes.

Formula & Notation

log [ion] ∝ E

Other Names / Synonyms: Potentiometric analysis, potentiometry, pH measurement (type), ion-selective electrode measurement

Properties & Characteristics

Potentiometry is an electroanalytical technique that measures the potential (voltage) of an electrochemical cell under zero-current conditions to determine the concentration or activity of analyte ions. The cell potential follows the Nernst equation: E = E° − (RT/nF)log[ion]. Common potentiometric sensors: pH glass electrode (H⁺), ion-selective electrodes (ISEs for Na⁺, K⁺, Ca²⁺, F⁻, Cl⁻, NO₃⁻), and reference electrodes (Ag/AgCl, saturated calomel).

Uses & Applications

Potentiometry is used in: pH measurement (pH meters in all laboratories and industries), clinical analysis (blood gas analysers, ISE for electrolytes: Na⁺, K⁺, Cl⁻ in blood), environmental monitoring (fluoride ISE for water analysis), food quality control (pH titration of cheeses, wines), and in titration end-point detection (potentiometric titrations).

Safety Information

Calomel reference electrodes contain mercury — handle carefully and dispose as hazardous waste. Concentrated potassium chloride electrolyte filling solutions are irritants. High-impedance pH meter circuits should be properly grounded to avoid interference. Some ion-selective electrode membranes (e.g., PVC-based) leach plasticisers into samples.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Potentiometry

Formula log [ion] ∝ E

Index All "P" terms

Synonyms Potentiometric analysis, potentiometry, pH measurement (type), ion-selective electrode measurement

Frequently Asked Questions

What is Potentiometry?

An electroanalytical technique that measures the potential (voltage) of an electrochemical cell to determine the concentration of a species in solution. The pH meter uses potentiometry with a glass electrode. Ion-selective electrodes extend potentiometry to many other analytes.

What is Potentiometry used for?

Is Potentiometry hazardous?

What is the formula for Potentiometry?

More "P" Terms

P-type Semiconductor Pairing Pairing Energy Palladium Pd Parachor [P] = M(γ)^(1/4) / (ρ_L - ρ_V) Paramagnetic χ_m > 0; unpaired electrons; μ = √(n(n+2)) BM (n = unpaired electrons) Paramagnetism Partial Ionic Character % ionic = (1 - e^(-Δχ²/4)) × 100% Partial Pressure Partial Pressure p_i = x_i × P_total; P_total = Σp_i Particulate Matter Parts Per Million ppm = mg/L (water) or mg/kg; = (mass solute/mass solution) × 10⁶

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