Silver, Gold, and More! Periodic Table Guide

The periodic table of chemical elements is an organized way for anybody to see the 118 known elements and understand their properties. The periodic table includes the atomic mass and chemical symbol for each element and may also include properties such as electronegativity, ionization energy, and atomic radius. It can be confusing at first glance, but before 1869, it was even more confusing, as scientists worked for years to determine what was the most effective way to organize the elements in a chart that would help people understand them. Dmitri Mendeleev created the version of the periodic table currently used today, though it has evolved over the past 150 years as we've developed a greater understanding of chemistry and physics.

The Legend

For those new to learning about the periodic table, it's best to obtain a copy that has a color-coordinated legend to help you learn the basics. The colors used may vary, but the categories are the same on every table.

The Numbers and Letters

Every element is listed within its own block and is identified with letters and numbers. The letters are the scientific abbreviations for each element. For example, "C" is carbon, "He" is helium, and "Ag" is silver. The number above the letters is called the atomic number, and it's the number of protons in a single atom of the element. The bottom number is the atomic mass; it represents the average weight of a single atom of that element.

Groups

Every vertical column on the periodic table is a group. There are 18 groups on the periodic table, one for every column. Elements in a group all have similar properties.

Periods

Since there is a vertical grouping of elements, it's important to note that there is a horizontal method of grouping them as well. These are called periods, and elements in each period also share certain properties. There are fewer periods in the table, only seven, compared to the 18 groups shown on the periodic table.

Increasing Atomic Number

Elements in the periodic table are listed in order of their atomic number from smallest to largest. Hydrogen is located in the top left of the periodic table with an atomic number of 1, and the numbers increase from left to right and top to bottom.

Atomic Radius (Atom Size)

The atomic radius is the distance between the nuclei of two identical atoms of an element that have bonded together. These measurements aren't often listed on the periodic table, but there's a trick to figuring out which ones are larger or smaller. The atomic radii are ordered from smallest to largest started at the top right and increasing from right to left and from top to bottom. This means that helium, in its spot at the top right of the table, has the smallest atomic radius, and the element at the bottom left, francium, has the largest atomic radius of the elements.

• Periodic Table of Chemical Elements
• The Periodic Table
• Interactive Periodic Table
• Periodic Table of the Elements in Pictures and Words
• Derivations of the Names and Symbols of the Elements
• Inside Out: The Periodic Table
• What the Values on the Periodic Table Mean
• Reading the Periodic Table of Elements
• How Are Elements Grouped on the Periodic Table?
• Families of the Periodic Table
• Periodic Table Groups
• How to Remember the Groups of the Periodic Table
• The Periodic Table: Differences Between Groups and Periods
• Why Is the Periodic Table Arranged in Columns and Rows?
• Groups and Periods
• Assembling the Modern Periodic Table
• What Is an Atomic Number? Definitions and Examples
• What Are Atomic Numbers and Atomic Weights?
• Periodic Trends
• Atomic Number, Atomic Mass, and Isotopes
• Periodic Trends: Ionization Energy, Atomic Radius, and Ionic Radius
• Atomic Radius
• Periodic Table of Elements: Atomic Radius