Learning about and teaching the Periodic Table of the Elements is integral to science education.
Understanding the Periodic Table
Here are some answers to common questions about the periodic table.
Why is it called a periodic table?
When Dmitri Mendeleev drew up the periodic table, he grouped elements of similar properties. Based on the number of electrons, a scientist can determine which group to place an element into. This pattern is called a period (or row) on the periodic table.
How do I read the periodic table?
The key to understanding the periodic table is in its layout. The table is comprised of seven rows (called periods), 18 columns (called groups or families). Some tables, like ours above, also include colors to help identify groups that cross rows and columns.
The colored areas of our table break up the elements into groups of alkali metals, alkaline earth metals, lanthanides and actinides, transition and post-transition metals, metalloids, nonmetals, halogens, and noble gases. We go indepth on each of these groups in the questions below.
How do I interpret the element boxes?
Located right above the English name for each element, the largest letters represent its chemical abbreviation. The largest number is the element’s atomic number. Other information in the box includes the element’s electron configuration, electronegativity, oxidation states, and its first ionization energy measured in kilojoules per mole.
What are the 118 elements?
An element, simply put, is a fundamental unit of matter that cannot be easily broken down. It consists of a specific number of protons and variable neutrons and electrons. All of matter is made of these 118 elements, combined in various ratios and kept in different states, like solids.
Depending on where you are in the universe, some are more prevalent. Here on Earth, elements like oxygen (O) and hydrogen (H) are common, but technetium (Tc) and nihonium (Nh) are rare.
Is there an element 119?
As of this writing, scientists have not isolated a stable element 119. Most elements were discovered naturally. However, heavier elements must be synthesized in a nuclear laboratory. Those larger than element 109 have all been formed and isolated this way.
Currently, the largest made is 118. Odd-numbered elements pose a greater challenge for isolation, as their nucleons are not as stable.
What are the rarest metals?
On the periodic table, there is a family of eight elements known as the precious metals, including elements 44 – 47 like silver and 76 – 79 like gold. These metals are considered to be both very rare and of high value.
Of those, the two most rare metals are rhodium (Rh) and osmium (Os). This means that they are not commonly found naturally on Earth or within the universe.
Why isn’t steel on the periodic table?
Different types of steel made add other elements to enhance properties. For example, chromium (Cr) may be added to increase steel’s hardness.
What are alkali metals?
The alkali metal family includes the six elements in the first column of the periodic table, from lithium (Li) down to francium (Fr). These metals all contain one valence electron, meaning they form cations and react readily with water. These elements form the ionic bonds known as salts.
Hydrogen (H) may be mistakenly placed into this family, but it does not contain any of the family traits.
What are alkaline earth metals?
The alkaline earth metals represent the second column on the periodic table. Its six elements extend from beryllium (Be) to radium (Ra). These metals are named for forming basic solutions when put into water. They tend to form cations with a positive two charge and bond ionically.
What are lanthanides and actinides?
The lanthanides and actinides refer to the two families of mostly radioactive metals in an off-shoot of the periodic table. Usually, they are shown as two rows on a separate section with the top row, elements 57 – 57, for the lanthanide and the bottom row, elements 89 – 103, for the actinides.
These metals have very unique properties, owing to their f-orbital arrangements and unstable nuclei. As an example, uranium (U) is a part of this group.
What are transition and post-transition metals?
The transition metals include 34 metals in the middle of the periodic table. These metals are named this way, as they can take on many different charges, due to their valence electrons being in the d-orbitals. As a result, these metals tend to have a wide variety of colors and properties.
The post-transition metals are those metals that come after the transition metals, but before the noble gases within a row. There are only eight of them, but they can take on some very unique properties, charges, and colors.
What are metalloids and nonmetals?
Metalloids are those seven elements that make up the stair-step line on the periodic table, including boron and silicon. These elements have properties similar to both metals and non-metals.
Metalloids can take on either a positive or negative charge, depending on what other elements are around. These elements are particularly important for the electronic community.
Nonmetals represent the top right of the periodic table. These elements are usually gases at room temperature and tend to form anions. Non-metals have the highest electronegativity of any of the elements, meaning they steal electrons.
What are halogens?
The halogen family is the main group seven on the periodic table, including fluorine down to astatine. They are all non-metals forming a singly charged anion. They represent all three states of matter.
What are the noble gases?
The noble gases are the nonmetals that do no react with any element unless extreme conditions are imposed. They are the rightmost column on the periodic table. They usually do not form compounds, as they have a full octet.
Why should commodity traders care about the periodic table?
Traders can also enhance their understanding of the overall commodity marketplace by using the periodic table to see possible relationships between metals and other chemicals that may affect their pricing.
Periodic Table Learning Resources
We’ve gathered additional resources to help teachers and students of all ages better understand the periodic table.
Quick Videos About the Periodic Table
- Periodic Table of Elements [Kahn Academy] – 11:21 – This free lesson explains how the table is organized.
- The Periodic Table Song [AsapSCIENCE] – 3:04 – A song to help you remember the elements.
Periodic Table Lesson Plans & Activities
- Understanding the Periodic Table of Elements : 10 Steps [Instructables] – A lesson plan to teach the table to young students.
- Periodic Table Teacher Resources [STEM Learning] – A good resource for homeschoolers.
- 7 of the Best Science Resources for Teaching the Periodic Table in KS3 Chemistry [TeachWire] – Lesson plans, printouts, and activities.
- Classroom Resources | The Periodic Table Unit Plan [American Association of Chemistry Teachers] – Resource library and multimedia collection.
- It’s Elemental – The Periodic Table of Elements [JLab Science Education] – Online games and activities to help students learn.
- Periodic Table of the Elements Lesson Plan [PBS Learning Media] – Scavenger hunt and other learning plans.