Question

what is lanthanides and actinides

Answer 1

The lanthanides and actinides are groups of elements in theperiodic table. They are the elements that are often listedbelow the main section of the periodic table. There are thirtytotal elements in the lanthanides and actinides. They areoften called the "innertransition metals."Lanthanides:-The lanthanides are the elements with atomic numbers from57 to 71. These 15 metals (along with scandium andyttrium) are often called the rare earth elements. They areall silvery-white metals which are often found in the sameores. They are called the lanthanides because they exhibitsimilar chemical properties to lanthanum, the first elementin the group.Actinides:-Actinides are the 15 elements with atomicnumbers from 89to 103. They are named after the first element in the series,actinium. The actinides group includes mostly man-madeelements with only a few exceptions such as uranium andthorium. The actinides are most known for the elementsuranium and plutonium which are used in nuclear reactorsand nuclear bombs.

Answer 2

Both are radioactive elements, forming two periods in the Periodic Table of Elements. They are called the first element of each period, "Lantanium and Actinium"