Moseley's X-ray spectrum

Moseley's X-ray spectrum refers to the observation made by physicist Henry Moseley in the early 20th century, which revealed a systematic relationship between the wavelengths of X-rays emitted by elements and their atomic numbers. By studying X-rays produced when atoms are bombarded, Moseley found that each element emits X-rays with distinct wavelengths, closely linked to its atomic number rather than its atomic mass. This discovery provided a foundation for modern periodic law and reinforced the concept that the atomic number is the defining characteristic of an element, revolutionizing the understanding of atomic structure and periodicity in the elements.