1. What is Electronvolt (eV)?

The electronvolt (eV) is a unit of energy equal to approximately 1.602×10⁻¹⁹ joules. It's commonly used in physics and chemistry to express small energies, especially in atomic and particle physics.

2. How Does the Calculator Work?

The calculator uses the conversion formula:

Where:

• \( Joules \) — Energy in joules (J)
• \( 1.60217662 \times 10^{-19} \) — Conversion factor from joules to electronvolts

Explanation: The equation converts energy from joules to electronvolts by dividing by the elementary charge.

3. Importance of eV Calculation

Details: Electronvolts are essential for understanding energy levels in atoms, band gaps in semiconductors, and particle physics experiments.

4. Using the Calculator

Tips: Enter energy in joules (must be positive value). The calculator will automatically convert to electronvolts.

5. Frequently Asked Questions (FAQ)

Q1: Why use electronvolts instead of joules?
A: Electronvolts provide a more convenient scale for atomic-scale energies where joules would be impractically small numbers.

Q2: What is the relationship between eV and mol?
A: 1 eV per particle equals approximately 96.485 kJ/mol (Faraday constant × elementary charge).

Q3: What typical energies are measured in eV?
A: Chemical bond energies (1-10 eV), photon energies in visible light (1.6-3.4 eV), semiconductor band gaps (0.1-10 eV).

Q4: Can I convert eV to other units?
A: Yes, eV can be converted to joules, calories, or other energy units using appropriate conversion factors.

Q5: Is eV an SI unit?
A: No, but it's accepted for use with SI units and commonly used in physics and chemistry.