Question

An atom emits a photon with energy 7.13 electronvolts (eV). What is the wavelength of the photon?

Answer 1

Answer:

Option (b) "174 nm"

Explanation:

Energy of emitted photon is 7.13 eV.

We need to find the wavelength of the photon.

1 eV = 1.6 × 10⁻¹⁹ J

Energy of a photon is given by :

$E=\dfrac{hc}{\lambda}$

Where, $\lambda$ is wavelength of the photon

Putting all the values,

$\lambda=\dfrac{hc}{E}\\\\\lambda=\dfrac{6.63\times 10^{-34}\times 3\times 10^8}{7.13\times 1.6\times 10^{-19}}\\\\\lambda=1.74\times 10^{-7}\ m\\\\\text{or}\\\\\lambda=174\ nm$

So, the wavelength of the photon is 174 nm.