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`E = (h*c)/lambda`

Enter a value for all fields

The **Energy of a Photon **calculator computes the energy of a photon based on the wavelength (λ), Plank's Constant (h), and the speed of light (c)

**INSTRUCTIONS**: Choose units and enter the following:

- (
**λ**) Wavelength of light

**Energy of a Photon(E):** The calculator returns the energy in Joules. However, this can be automatically converted to compatible units via the pull-down menu.

Certain conditions make it possible to describe light as a particle, or **photon ^{[1]}**. The energy of each photon of light corresponds to a specific frequency. This relationship is described by Planck's equation:

where

- E is the energy of the photon
- h is Planck's constant
- c is the speed of light ( 2.998 × 10
^{8}m/s) - λ is the wavelength of the light

You see a green light with a wavelength of 530nm. Calculate the energy, in joules, associated with a photon of this light.

First, we define our variables:

- λ = 530nm = 5.3 x 10
^{-7}m - h = 6.626 × 10
^{-34}joules*s - c = 2.998 × 10
^{8}m/s

E=(hc)/λ

Next, we substitute in our values and calculate the energy:

E = (6.626 × 10 ^{-34} joules*s)(2.998 × 10^{8} m/s) / (5.3 x 10^{-7}m)

E = 3.748 x 10^{-19} joules

Whitten, et al. "Chemistry" 10th Edition. Pp. 137

Chemistry Worksheet: Planck's Equation

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