Chemistry

Noble gases have a full valence shell of electrons, which makes them highly stable and unreactive compared to other elements.

Rare earth elements mostly comprise the lanthanide series, which are key components in various electronic devices and are known for their magnetic and luminescent properties.

While Mendeleev’s table was organized by increasing atomic mass, the modern table is organized by increasing atomic number, which resolves many of the inconsistencies in the earlier arrangements.

Moseley's discovery established the atomic number as the basis for organizing the periodic table, leading to a clearer and more accurate understanding of element properties and their relationships.

The modern periodic table helps predict the chemical behavior of elements, organize elements with similar properties, and guide the discovery of new elements. It is a critical tool for chemists.

As you move across a period, the number of protons increases, which increases the nuclear charge. This pulls the electrons closer to the nucleus, reducing the atomic radius.

Periods are horizontal rows, and groups are vertical columns. Elements in the same period have the same number of electron shells, while elements in the same group have the same number of valence electrons.

The periodic law states that the properties of elements are a periodic function of their atomic numbers. This means that elements show recurring patterns in their properties when arranged by atomic number.

Elements are arranged in increasing order of their atomic number (number of protons). This arrangement leads to periodic trends in properties such as atomic radius, ionization energy, and electronegativity.