Periodic Table Overview and History

A table that organizes elements by increasing atomic number, with elements in the same group sharing similar properties.

The vertical columns of the periodic table, containing elements with similar chemical properties.

The horizontal rows of the periodic table, displaying elements with increasing atomic number.

The repeating patterns in the chemical and physical properties of elements when arranged by atomic mass are termed periodicity.

Rearranged elements in the periodic table by increasing atomic number rather than atomic mass using X-ray experiments.

A tabular arrangement of the chemical elements, organized by atomic number, electron configuration, and recurring chemical properties.

Proposed that atoms of the same element have the same characteristics, assigned some atomic weights to first elements.

International Union of Pure and Applied Chemistry, updating and overseeing the periodic table.

The tendency of an atom to attract electrons in a bond increases moving up and to the right on the periodic table.

The energy needed to remove an electron from an atom increases moving up and to the right on the periodic table.

The energy released when an atom gains an electron increases moving up and to the right on the periodic table.

Important organic compounds for life, like lipids, nucleic acids, carbohydrates, and proteins.

Small molecules that combine to form larger polymers.

Organic compounds made of carbon, hydrogen, and oxygen, providing energy and structure in living organisms.

The basic unit of carbohydrates, like glucose, fructose, or galactose.

Two monosaccharide molecules bonded together, like sucrose or lactose.

Elements belonging to the s and p blocks of the periodic table, showing a wide range of chemical properties.

An element's tendency to lose electrons and form positive ions (cations), often accompanied by good conductivity, malleability, and luster.

An element's tendency to gain electrons and form negative ions (anions), typically resulting in poor conductivity, brittleness, and dull appearance.

The distance from the nucleus to the outermost electron shell of an atom, measured as half the distance between two identical atoms bonded together.

Electronegativity increases from left to right across a period, as atoms become smaller and more attractive to electrons.

Electronegativity decreases from top to bottom within a group, as electrons are further away from the nucleus and less attracted.

Metallic property increases down a group, as electrons are further from the nucleus and more easily lost.

Metallic property decreases across a period, as electrons are more tightly bound to the nucleus.

Atoms tend to gain, lose, or share electrons to achieve a stable configuration with eight valence electrons, similar to noble gases.

A representation of an atom's valence electrons using dots around its symbol, showing how they participate in bonding.

Electrons in the outermost energy level of an atom, involved in chemical bonding.

Atoms or groups of atoms that have gained or lost electrons, resulting in a net positive or negative charge.

Monoatomic ions are single atoms with a charge, while polyatomic ions consist of multiple atoms bonded together and carrying a charge.

Electrons that occupy the outermost shell of an atom. These electrons are involved in chemical bonding and determine an element's reactivity.

The tendency of atoms to gain, lose, or share electrons to achieve a stable configuration with eight electrons in their outermost shell.

Complex carbohydrates made of many monosaccharide units linked together. Examples include starch, glycogen, and cellulose.

Glycerol and fatty acids are the basic units. Fatty acids are long hydrocarbon chains with a carboxyl group. Glycerol is a three-carbon molecule that combines with fatty acids to form triglycerides.

Proteins are large molecules made of long chains of amino acids.

Large biomolecules responsible for storing and transmitting genetic information. They are made up of nucleotides.

Carbon, hydrogen, and oxygen are the key components. They provide energy and structure in living organisms.

Proteins contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur.