Metalloid Elements on the Periodic Table: Definition & Properties

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Thallium: Uses, Facts & Properties

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:00 The Periodic Table
  • 0:38 The Metalloids
  • 1:10 Properties of Metalloids
  • 3:01 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Megan Wahl

Megan has taught middle school science and developed curriculum for k-higher ed. She has a master's degree in Educational Technology.

The metalloid elements are found in the middle of the periodic table at the point where the metals and nonmetals meet. In this lesson, you'll learn the definition of a metalloid, as well as the properties that these unique elements possess.

The Periodic Table

The periodic table is a chart used by scientists to understand all of the elements that exist in our world. The elements in the table are broken down into different groups based on specific and shared traits and are classified by their chemical and physical properties, color, and texture, how well they conduct electricity, and how they bond with other elements. Most of the elements in the periodic table are either a metal or a nonmetal, but some have shared properties of both metals and nonmetals and are called the metalloids. At the point where the metals and nonmetals meet on the table, you can find the metalloids.

The Metalloids

The metalloids are a unique group of elements that share properties of both metals and nonmetals. They're also called the semimetals because of the shared properties of these elements along the dividing line between metals and nonmetals. The elements that may be classified as metalloids include:

  • Boron_ (B)
  • Silicon (Si)
  • Germanium (Ge)
  • Arsenic (As)
  • Antimony (Sb)
  • Tellurium (Te)
  • Polonium (Po)
  • Astatine (At)

Properties of Metalloids

How would you know if you were looking at a metalloid? Most metalloids are solid at room temperature. If you were able to observe a metalloid up close, it might appear brittle, such as this sample of boron.

Some also have a shiny, metallic appearance, like this sample of silicon.

Some metalloids are ductile, meaning that they can be stretched out into a thin wire easily. Some of the metalloids are also malleable, meaning that they're shaped into new forms easily without breaking.

Depending on the temperature where they are found, metalloids can act as either an electrical insulator or an electrical conductor. An insulator is a material that stops the flow of electrons, such as the plastic material surrounding wires. A conductor is a material that electrons flow through easily. Scientists often call metalloids semiconductors because they're somewhat good at conducting electricity. At mild temperatures, metalloids tend to act as good insulators. When the temperature gets warmer and they heat up, they tend to conduct electricity much better.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account