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The Periodic Table

Periodic Table Trends

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Melting point of group 1A
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The periodic trend is a property that changes predictably as you move across a row or down a group.
 
The periodic table is organized into periods(rows) and groups(columns). Elements found in a group have similar properties. The elements are placed in four of the groups: the alkali metals, alkaline earth metals, halogens, and noble gases. Metals are found on the far left side of the periodic table. These metals are conductors of heat and electricity. Nonmetals are found on the upper right side of the periodic table, they possess a diverse set of properties.
 
The elements of the periodic table can be classified into three main groups. The groups are: metals, semimetals or metalloids, and nonmetals.

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 "The way in which electrons are distributed among the various orbitals is called the electron configuration."

 "Orbitals are filled in order of increasing energy, with no more than two electrons per orbital."

 "The electron configuration of an atom is a form of notation which shows how the electrons are distributed among the various atomic orbital and energy levels.  The format consists of a series of numbers, letters and superscripts."

 "The number of sublevels that an energy level can contain is equal to the principle quantum number of that level." 

 "An orbital is a space that can be occupied by up to two electrons.  Each type of sublevel holds a different number or orbitals, and therefore, a different number of electrons.  s sublevels have one orbital, which can hold up to two electrons.  p sublevels have three orbitals, each of which can hold 2 electrons, for a total of 6.  d sublevels have 5 orbitals, for a possible total of 10 electrons.  f sublevels, with 7 orbitals, can hold up to 14 electrons."

 "An easy way to calculate the number of orbitals found in an energy level is to use the formula n2."

 "An easy way to calculate the total number of electrons that can be held by a given energy level is to use the formula 2n2."

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Certain characteristics follow trends when going across the different rows or down the columns in the periodic table. Moving towards the right across a single row of the table one electron experiences more of an attraction to the nucleus because of the positively charged nucleus. During this process the electrons are more compacted around the nucleus towards the right. This means that the radius of an atom decreases moving from left to right. Going down a group(column-wise) means that you are adding more shells of electrons, the size of the atom becomes larger.
 
Electronegativity and ionization normally increases across the rows and decreases down a group.
 
 

Ionization is: "The formation of or separation into ions by heat, electrical discharge, radiation, or chemical reaction." Electronegativity is: "The tendency of an atom or radical to attract electrons in the formation of an ionic bond"
 
 
 

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Alkali metals are extremely reactive. They contain one valence electron each. Alkali metals have a very soft consistency. The alkaline earth metals contain positive "electron affinities." They also have two valence electrons. Transition metals have many different states they can be in. They can give up their electrons very easily and also have some to lose. Halogens only need one additional electron to complete their outer shells, and thus, they form bonds incredibly fast. The noble gases are elements that do not form compounds.

The Joke Of The Page
 
* " What do you do when you find a dead chemist?"
 
 
 
* " You Barium"