Introduction to Chemistry

Summary:

The text provides an overview of the periodic table and the properties of its elements. It explains how elements’ physical and chemical properties vary based on their electron configurations. The atomic number, representing the number of protons in the nucleus, determines the number of electrons in an atom. Electrons occupy different energy levels or shells, each accommodating a maximum number of electrons. The electron configuration refers to the distribution of electrons in an atom, with valence electrons responsible for the chemical properties. The periodic law states that elements’ properties are periodic functions of their atomic numbers, resulting in different chemical and physical properties among elements. The periodic table organizes elements based on their increasing atomic numbers, with elements having similar outer electron configurations forming groups and elements with the same number of electron shells constituting periods. The text discusses specific groups of elements, such as alkali metals, alkaline earth metals, halogens, noble gases, and transition metals, highlighting their characteristics and properties. It also mentions metalloids, which exhibit properties of both metals and nonmetals. The size of an atom is determined by factors like nuclear charge, core shells, and shielding effect, influencing atomic radius. The atomic radius generally decreases across a period and increases down a group on the periodic table. The text also briefly mentions atomic properties, including atomization energy and size.

Excerpt:

Introduction to Chemistry

The elements on the periodic table exhibit gradual variation in the following properties.
1. Atomization
2. Ionic size
3. Ionization
4. Electron affinity
5. Electronegativity is the same as the enthalpy of atomization.

Periodic Chemistry is a study of how the physical and chemical properties of elements in general, for which some examples are argon, magnesium, and aluminium, vary with different electron configurations; in other words, the physical and chemical properties of Aluminum are different from that of Nitrogen because of the difference in their electron configuration (arrangements), that is to say if all elements have the same electron configuration. They would have the same chemical and physical properties. The atomic number is the number of protons in the nucleus of an atom.