Differences Between Transition Metals & Inner Transition Metals

Scientists handle inner transition elements carefully because many are explosive.
••• Jupiterimages/Comstock/Getty Images

Transition metals and inner transition metals appear to be similar in the way they are categorized on the periodic table, but they have significant differences in their atomic structure and chemical properties. The two groups of inner transition elements, actinides and lanthanides, behave differently from each other as well, even though they are both considered rare earth elements.

Atomic Number

The number of protons in the nucleus of an atom determines its classification and position on the periodic table because each element is unique and has a unique atomic number. The transition metals appear as numbers 21 through 116 on the chart. This range includes the inner transition metals.

Atomic Structure

Although transition metals and inner transition metals have the same atomic structure, the electrons fill their orbitals in different ways, which affects the size of the atom. Inner transition metals also give up their electrons more easily. Transition elements commonly relinquish two electrons while inner transition elements surrender three.


The fifteen metals called lanthanides occupy atomic numbers 57 -- lanthanum -- through 71 -- lutetium -- on the periodic table. They react similarly, so they are grouped together. They’re soft, malleable, ductile and chemically reactive elements that burn easily in air and have many industrial uses.


This series of chemically similar metallic elements have atomic numbers ranging from 89 -- actinium -- to 103 -- lawrencium. All of these elements are radioactive. Scientists use two of them, uranium and plutonium, to generate nuclear energy. Actinides beyond uranium are all synthetic.

Related Articles

How the Elements Are Classified on the Periodic Table
Why Is the Periodic Table Arranged in Columns & Rows?
Parts of the Periodic Table
Difference in Properties of Main Group & Transition...
Why Do Compounds of Metals & Nonmetals Consist of Ions?
Do Metal Atoms Lose Their Valence Electrons When Forming...
Relationship Between the Atomic Number and the Chemical...
What Are the Similarities Metals & Nonmetals Have in...
What Is a Noble Gas Configuration?
What Are Inner Shell Electrons?
Characteristics of Ionic and Covalent Compounds
How Is the Periodic Table Organized?
How to Find the Mass Number of Bromine With 46 Neutrons
Types of Metals on the Periodic Table
Which of the Metalloids Has the Smallest Atomic Radius?
How to Read the Periodic Table for Kids
What Determines Whether an Ion Will Form?
How to Make a 3-D Bohr Model
How to Calculate Valence
The Effects of Acid on Different Kinds of Metal