The organization of elements on the periodic table in order of increasing atomic number is based on experimental observations and the understanding of atomic structure.
The concept of atomic number, which represents the number of protons in the nucleus of an atom, was developed by Henry Moseley in the early 20th century. Moseley's work involved studying X-ray spectra emitted by different elements. He found that the frequencies of X-rays emitted by elements correlated directly with their atomic numbers, rather than their atomic masses or other properties.
This discovery provided strong evidence that the atomic number is the fundamental property that determines an element's position in the periodic table. It revealed a direct relationship between the atomic number and the element's electronic structure, which governs its chemical behavior and properties.
Since Moseley's discovery, further experimental studies, such as spectroscopy and mass spectrometry, have confirmed the organization of elements based on atomic number. These techniques allow scientists to measure and analyze the fundamental properties of elements, including their atomic number, atomic mass, and electronic structure.
The periodic table's organization in increasing atomic number provides a systematic arrangement of elements that reflects the periodicity of their properties. It allows for the identification of trends and patterns in the chemical behavior and properties of elements, enabling scientists to predict and understand the properties of unknown elements based on their position in the table.
Overall, the order of elements in the periodic table based on increasing atomic number is supported by extensive experimental evidence and serves as a foundational principle in modern chemistry.