Which of the Metalloids Has the Smallest Atomic Radius?

Boron is a Period Two metalloid.
••• Jupiterimages/Photos.com/Getty Images

The metalloids are elements that display some properties of both metals and nonmetals. The exact list of metalloids is not agreed upon. However, boron, silicon, germanium, arsenic, antimony and tellurium are all frequently classified as metalloids. Boron has the smallest atomic radius of these metalloids.

Periodic Trends in Atomic Radius

Atomic radius increases as you move vertically down the periodic table. As you move down a group of the periodic table, each new row indicates the addition of an energy level. This increases the average distance of the outermost electron from the nucleus. However, atomic radius decreases as you move from left to right across a period of the periodic table. The protons and electrons in an atom increase, but the electrons fill valence shells in the same energy level. The electron cloud does not grow substantially in size, but the net charge of the nucleus does. Hence, the electrons are pulled closer to the nucleus and the atomic radius decreases.

Related Articles

Why Do Valence Electrons Affect the Atomic Radius of...
What Does the Period Number Represent?
What Affects the Atomic Radius?
Why Is the Periodic Table Arranged in Columns & Rows?
Which Halogen Has the Least Attraction for Electrons?
Relationship Between the Atomic Number & the Chemical...
Why Does the Boiling Point Increase When the Atomic...
How to Find Isotope Mass
Relationship Between the Atomic Number and the Chemical...
Particles That Are Smaller Than an Atom
How to Find the Mass Number of Bromine With 46 Neutrons
How to Find Out If an Element Is an Ion
Differences Between Transition Metals & Inner Transition...
How to Determine the Highest Ionization Energy
What Are an Atom, Electron, Neutron and Proton?
Differences in Properties of Halogens & Hydrogen
Atomic Number Vs. Atomic Density
How to Find Isotopes
How the Elements Are Classified on the Periodic Table