The Bohr model can also be used to predict an approximate radius for an atom. The equation for the radius r of the hydrogen atom is:r=πme2h2kwherem=" mass of electron "A student suggests that, for a speed of 1.4×107ms−1, neutrons would have a wavelength similar to the radius of a hydrogen atom.Determine whether the student is correct." mass of neutron "=1.67×10−27kg
Q. The Bohr model can also be used to predict an approximate radius for an atom. The equation for the radius r of the hydrogen atom is:r=πme2h2kwherem=" mass of electron "A student suggests that, for a speed of 1.4×107ms−1, neutrons would have a wavelength similar to the radius of a hydrogen atom.Determine whether the student is correct." mass of neutron "=1.67×10−27kg
Use formula for neutron: Use the de Broglie wavelength formula for the neutron: λ=mvh, where h is Planck's constant, m is the mass of the neutron, and v is the velocity of the neutron.
Plug in values: Plug in the values: h=6.626×10−34 J⋅s (Planck's constant), m=1.67×10−27 kg (mass of neutron), and v=1.4×107 ms−1 (velocity of neutron).
Calculate wavelength: Calculate the wavelength λ: λ=1.67×10−27 kg×1.4×107 ms−16.626×10−34 J⋅s.
Perform calculation: Perform the calculation: λ=1.67×10−27×1.4×1076.626×10−34=2.82×10−10 meters.
Compare to hydrogen atom radius: Compare the calculated wavelength of the neutron to the known radius of the hydrogen atom, which is approximately 5.29×10−11 meters.
Conclusion: The wavelength of the neutron is much larger than the radius of the hydrogen atom, so the student's suggestion is incorrect.