Lanthanum is the third element in Row 6 of the periodic table. The periodic table is a chart that shows how chemical elements are related to each other. Lanthanum is a transition element in Group 3 (IIIB) of the periodic table. Lanthanum's position makes it one of the transition metals. The transition metals are found in the center of the periodic table, in Groups 3 through 12.
Lanthanum can also be classified as a rare earth element. The rare earth elements are the 15 elements that make up Row 6 of the periodic table. That group of elements is also called the lanthanides. Either way of classifying Lanthanum is acceptable to most chemists.
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