1. What is the Energy Calculation in Chemistry?

Definition: This calculator determines the energy of a photon based on its wavelength using Planck's equation.

Purpose: It helps chemists and physics students understand the quantum energy associated with electromagnetic radiation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( E \) — Energy of the photon (joules)
• \( h \) — Planck's constant (6.626 × 10⁻³⁴ J·s)
• \( c \) — Speed of light (3 × 10⁸ m/s)
• \( \lambda \) — Wavelength of the radiation (meters)

Explanation: The energy of a photon is inversely proportional to its wavelength - shorter wavelengths correspond to higher energy photons.

3. Importance of Energy Calculation

Details: This calculation is fundamental in spectroscopy, quantum chemistry, and understanding atomic/molecular transitions.

4. Using the Calculator

Tips: Enter the wavelength in meters (e.g., 500 nm = 5e-7 m). The calculator uses fixed values for Planck's constant and speed of light.

5. Frequently Asked Questions (FAQ)

Q1: What are typical wavelength values?
A: Visible light ranges from 380-750 nm (3.8e-7 to 7.5e-7 m). X-rays are ~1e-10 m, radio waves can be meters to kilometers.

Q2: Can I calculate wavelength from energy?
A: Yes, rearrange the formula: λ = (h × c)/E

Q3: Why is the energy value so small?
A: Planck's constant is extremely small (10⁻³⁴ scale), so photon energies are tiny in joules. Chemists often use electronvolts (eV) instead.

Q4: Does this work for all electromagnetic radiation?
A: Yes, the formula applies to all photons from radio waves to gamma rays.

Q5: How precise are the constants used?
A: The values are standard physical constants with many significant digits, but we use 3 significant figures for simplicity.