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It takes 475 kJ to remove one mole of electrons from the atoms at the surface of a solid metal.

What is the maximum wavelength of light capable of doing this?

m

User Hendryanw
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Answer:

λ ≈ 4.18 x 10^(-7) meters

Step-by-step explanation:

The energy required to remove an electron from an atom is related to the energy of the photon that can do this through the use of the photoelectric effect equation:

E = h * f

Where:

E is the energy of the photon

h is Planck's constant (approximately 6.626 x 10^(-34) J·s)

f is the frequency of the light

To find the maximum wavelength (λ) of light capable of removing an electron, we can use the speed of light (c) equation:

c = λ * f

Where:

c is the speed of light (approximately 3.00 x 10^8 m/s)

λ is the wavelength of light

f is the frequency of light

We can rearrange this equation to find the frequency:

f = c / λ

Now, we can substitute this expression for frequency into the energy equation:

E = h * (c / λ)

We know that the energy required to remove one mole of electrons is 475 kJ (1 kJ = 1000 J) and we have Planck's constant (h) and the speed of light (c). We need to convert 475 kJ to joules:

475 kJ = 475 * 1000 J = 475,000 J

Now, we can solve for λ:

475,000 J = (6.626 x 10^(-34) J·s) * (3.00 x 10^8 m/s) / λ

Now, solve for λ:

λ = (6.626 x 10^(-34) J·s) * (3.00 x 10^8 m/s) / 475,000 J

λ ≈ 4.18 x 10^(-7) meters

So, the maximum wavelength of light capable of removing an electron from the surface of the solid metal is approximately 4.18 x 10^(-7) meters, or about 418 nanometers (nm). This falls within the ultraviolet part of the electromagnetic spectrum.

User Enle Lin
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