What is the largest unit of charge?

Units of Electric Charge

• The SI unit of electric charge is the coulomb (C).
• Charge can also be expressed in ampere-hours (Ah), especially when dealing with batteries.
• In chemistry, the unit faraday (F) is often used to measure charge transferred during electrolysis.

Coulomb (C)

• In the International System of Units (SI), 1 coulomb = 1 ampere × 1 second (1 A·s).
• It represents the quantity of charge carried by approximately 6.24 × 10¹⁸ electrons (or charge carriers).
• The coulomb is the standard and preferred unit for measuring electric charge.

Faraday (F)

• 1 faraday ≈ 96,500 coulombs.
• It represents the charge of 1 mole of electrons (Avogadro’s number of electrons).
• The faraday is especially important in electrochemistry, as it denotes the charge required to deposit or liberate one mole of a substance during electrolysis.
• Named after Michael Faraday, one of the pioneers of electromagnetism and electrochemistry.
• Sometimes referred to as the Faraday constant.

Conversion

• To convert coulombs → faradays, divide by 96,500.
• To convert faradays → coulombs, multiply by 96,500.

Other Units of Charge

• The smallest unit of charge in electrostatics is the franklin (esu of charge).
• 1 franklin ≈ 3.3356 × 10⁻¹⁰ coulombs.

Summary:

• SI unit: Coulomb (C)
• Larger chemical unit: Faraday (F = 96,500 C)
• Smallest electrostatic unit: Franklin (1 Fr ≈ 3.34 × 10⁻¹⁰ C)