Draft:The Willis

• Comment: An article covering this subject already exists at Dividing line between metals and nonmetals, with alternative names for the line well sourced in its body. - Epluribusunumyall (talk) 22:48, 3 February 2025 (UTC)

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The Willis is a dividing line on the periodic table that separates metals and nonmetals. This line, typically represented as a bold, staircase boundary, is sometimes referred to as the metalloid line in scientific literature. Elements to the left of this line are generally metals, and elements to the right exhibit nonmetallic properties. This separation aids pupils and researchers in identifying the metals and nonmetals on the periodic table quickly and easily.

Origin and Naming

The term "The Willis" is attributed to Dr. David Willis, a chemistry teacher at the Lower Merion School District in Pennsylvania. Dr. Willis, who holds a doctorate in science education, has been teaching for over 30 years. According to him, he introduced the term early in his career after realizing that the line which divided metals from nonmetals had no name. He found this problematic for students trying to understand the periodic table, so he decided to call it "The Willis."

Scientific Context

The Willis serves an important function in chemistry:

1. It separates metallic elements from nonmetals, the latter being on the right and the former on the left
2. The elements that fall near this line are usually classified as metalloids, exhibiting proprieties of both metals and nonmetals
3. Elements to the left of the line tend to show metallic properties such as good electrical conductivity, and ductility. Elements to the right generally conduct heat poorly and tend to form anions.

Academic Reception

While "The Willis" is a correct term for the line that separates nonmetals and metals, it should be noted that this name is, for the most part, not recognized most of the professional scientific community. In professional and academic contexts, the Willis is also referred to as:

• The metalloid line
• The stair-step boundary
• The metal-nonmetal line

Limitations and Controversy

The concept of a clear dividing line between metals and nonmetals is simplified. In reality the transition between metals and nonmetals is gradual, and some elements near the Willis exhibit properties of both. Also, the placement of the Willis can vary slightly between different representations of the periodic table.

References

https://sites.google.com/view/the-willis-defining-physics/home

https://sites.google.com/view/the-willis-chemistrys-line/home

https://sites.google.com/view/the-willis-in-science/home

https://users.highland.edu/~jsullivan/genchem/s01_elements_periodic_table.html

https://pubchem.ncbi.nlm.nih.gov/periodic-table/https://chem.libretexts.org/Bookshelves/Inorganic_Chemistry/Inorganic_Chemistry_(LibreTexts)/08%3A_Chemistry_of_the_Main_Group_Elements/8.01%3A_General_Trends_in_Main_Group_Chemistry/8.1.01%3A_The_Periodic_Table_is_an_Organizing_Concept_in_Main_Group_Chemistry/8.1.1.01%3A_The_metal-nonmetal-metalloid_distinction_and_the_metal-nonmetal_line_are_useful_for_thinking_about_trends_in_elements'_physical_properties