MODERN PERIODIC TABLE
The periodic table is a tabular arrangement of the chemical elements organized on the basis of their atomic numbers, electron configurations, and chemical properties.
Elements are presented in order of increasing atomic number (the number of protons in the nucleus). The standard form of the table consists of a grid of elements laid out in 18 columns and 7 rows, with a double row of elements below that. (Please see periodic table provided above.)
The horizontal rows of the table are called periods and the vertical columns are called groups. The periodic table incorporates recurring trends and can therefore be used to derive relationships between the properties of the elements and predict the properties of new, yet to be discovered or synthesized, elements. As a result, a periodic table provides a useful framework for analyzing chemical behavior.
Main group (or representative) elements include elements (except hydrogen) in groups 1 and 2 and groups 13 to 18. In older nomenclature, the main group elements are groups lA and lIA, and groups IIIB to O (CAS groups IIIA to VIIIA).
The elements in groups 3 to 12 are the transition elements, the focus of this exercise.
Transition elements are divided into two groups:
the transition metals
the inner transition metals
The two sets of inner transition metals are located along the bottom of the periodic table and are known as the lanthanide series and the actinide series. (See periodic table provided above.) The rest of the elements in groups 3 to 12 are transition metals.
Transactinide elements (also called transactinides, or super-heavy elements) are the elements with atomic numbers greater than those of the actinides. (The heaviest actinide is lawrencium (103).)
Transuranium (or transuranic) elements are those elements having an atomic number greater than that of uranium (92), an actinide. (Thus all transactinide elements are also transuranium elements.)
Transuranium elements are unstable and decay radioactively into other elements.
These elements were all first discovered in the laboratory, with neptunium, plutonium, americium, curium, berkelium, and californium later also discovered in nature.
Transuranium elements can be synthesized in the laboratory through the use of nuclear reactors or particle accelerators.
Please review the following questions:
1. Are all transactinide elements transuranium elements?
2. Are all tranuranium elements actinides?
3. List two unique properties of transuranium elements:
A.
B.
For the following symbols, provide the element name and indicate whether it is a representative element, a lanthanide, an actinide, or a transactinide element.
4. Cf
5. Pm
6. Ag
7. Ds
8. Tb
9. Rf
10. U
