Who discovered the atomic number based on X-ray wavelength in 1913?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. Henry Moseley.
- The atomic number based on X-ray wavelengths was discovered by Henry Moseley in 1913.
- Moseley's work demonstrated that the atomic number of an element is more fundamental than its atomic weight in determining its properties.
- He used X-ray spectroscopy to study the characteristic X-rays emitted by different elements and found that the frequency of the X-rays was directly related to the atomic number of the element.