Calorie to Electron Volt Converter

A calorie (cal), also called a small calorie or gram calorie, is a unit of energy equal to approximately 4.184 joules. It represents the energy needed to raise the temperature of one gram of water by one degree Celsius at standard atmospheric pressure.

The calorie was defined by French chemist Nicolas Clément in 1824 as a unit for measuring heat. It was widely used in chemistry and physics for calorimetry and thermodynamics before being largely replaced by the joule in scientific applications, though it remains in use for food energy.

Calories are primarily used in chemistry for small-scale energy measurements, in some scientific literature, and occasionally in food and nutrition contexts. However, they've been largely replaced by joules in scientific applications and by kilocalories (food calories) in nutrition.

An electron volt (eV) is a unit of energy equal to approximately 1.602 × 10⁻¹⁹ joules. It represents the kinetic energy gained by an electron when accelerated through an electric potential difference of one volt.

The electron volt was introduced in the early 20th century with the development of atomic and nuclear physics. It provided a convenient energy scale for atomic and subatomic processes, where joules would result in extremely small numbers with many decimal places.

Electron volts are extensively used in atomic physics, nuclear physics, particle physics, and materials science. They're standard for measuring atomic binding energies, photon energies, particle accelerator energies, and electronic band gaps in semiconductors.