Pre-Test
Q&A	The Periodic Table Chemical Bonding

Instruction 1-4

Connection Among the Location in the Table, the Atomic Number, and Mass | How to Identify Metals, Semimetals, Nonmetals, and Halogens | How to Identify Alkali Metals, Alkaline Earth Metals, and Transition Metals | Lanthanide, Actinide, Transactinide, and Transuranium Elements | Ionization Energy, Electronegativity, Relative Sizes | How Many Electrons Can Bond? | Size and Mass | Location and Quantum Electron Configuration | Summary

The first row consists of the Lanthanides, http://www.chemtopics.com/elements/lan/lan.htm  from lanthanum (La #57) to ytterbium (Yb #70), which should be placed on row 6. All Lanthanides are metals, but they’re very rare.

The last row of elements consists of the Actinides, http://www.infoplease.com/ce6/sci/A0802378.html  from actinium (Ac #89) to nobelium (No #102), which should be placed on row 7. Actinides are so rare as to be of little interest except for Uranium (U) and Plutonium (Pu) which are used in nuclear reactors.

Which reminds us – all elements larger than bismuth (Bi #83) are radioactive, and given enough time (in some cases, billions and billions of years, for some they’re gone in less than a second), will completely disappear from the universe. There are also some radioactive forms of the other elements.

Transactinide and Transuranium
http://en.wikipedia.org/wiki/Transactinide

The elements larger than uranium (#92) are considered transuranium elements. http://web.fccj.org/~ethall/uranium/uranium.htm  Twenty-four of these elements, up to and including atomic number 116, have been discovered. Eleven of them, from neptunium through lawrencium, belong to the actinide series. The other thirteen, which have atomic numbers higher than 103, are referred to as the transactinides. All the transuranium elements are unstable, decaying radioactively, with half-lives that range from tens of millions of years to mere fractions of a second. Since only 2 of the 20 have been found in nature (neptunium and plutonium) and those only in trace amounts, the synthesis of these elements through nuclear reactions has been an important source of knowledge about them.

Rare Earth Elements (Metals)
http://en.wikipedia.org/wiki/Rare-earth_metals 
There is a group of 17 metals that are designated as Rare Earth Elements. The 17 elements are scandium (21), yttrium (39), and the lanthanides (57 to 70), including lutetium (71). Promethium (61) shouldn’t be included since it does not occur naturally on earth. Some people may also include the actinides, but only 3 of them exist naturally. To summarize, the Rare Earth Elements occur in Group 3 (IIIB) and the lanthanides.

for Students, Parents and Teachers

Now let's do Practice Exercise 1-4 (top). 

Next Page:  Ionization Energy, Electronegativity, Relative Sizes (top)