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 atomic, nuclear, and particle physics, representing the amount of energy gained by a single electron when it accelerates through an electric potential difference of one volt.

2. How Does the Calculator Work?

The calculator uses the conversion formula:

For molar quantities:

Where:

• 1 eV = 1.60217662 × 10⁻¹⁹ J (exact by definition)
• 1 J = 6.241509074 × 10¹⁸ eV
• 1 eV/mol = 96.485 kJ/mol

3. Importance of Energy Conversion

Details: Converting between joules and electronvolts is essential in physics and chemistry, particularly when working with atomic-scale energies where eV is more convenient than joules.

4. Using the Calculator

Tips: Enter energy in joules (required) and optionally the amount in moles to get energy per mole. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why use eV instead of joules in physics?
A: Electronvolts provide a more convenient scale for atomic and particle physics where typical energies are on the order of eV to MeV.

Q2: How does this relate to chemistry?
A: In chemistry, energies per mole (eV/mol) are often used to describe reaction energies or bond strengths.

Q3: What's the difference between eV and eV/mol?
A: eV is an absolute energy unit, while eV/mol expresses energy per amount of substance (useful in chemistry).

Q4: Can I convert eV to other units?
A: Yes, 1 eV = 1.602×10⁻¹⁹ J = 96.485 kJ/mol = 23.061 kcal/mol.

Q5: What's a typical eV range in physics?
A: Atomic transitions: 1-10 eV, chemical bonds: ~1 eV, nuclear reactions: MeV range.