Periodic table groups and valence electrons

In chemistry, a valence electron is an electron that is associated with an atom, and that can participate in the formation of a chemical bond; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair. s chemical properties and whether it may bond with other elements: For a main group element, a valence electron can only be in the outermost electron shell.
In a transition metal, a valence electron can also be in an inner shell.
An atom with a closed shell of valence electrons (corresponding to an electron configuration s2p6) tends to be chemically inert.
An atom with one or two valence electrons more than a closed shell is highly reactive, because the extra valence electrons are easily removed to form a positive ion.
An atom with one or two valence electrons fewer than a closed shell is also highly reactive, because of a tendency either to gain the missing valence electrons (thereby forming a negative ion), or to share valence electrons (thereby forming a covalent bond).
Like an electron in an inner shell, a valence electron has the ability to absorb or release energy in the form of a photon. s valence shell; this is known as atomic excitation.

Groups, Families, Periods and Valence of the Periodic Table

What are Groups? 

• A group is a vertical column in the Periodic Table of Elements. They are considered the most important method in classifying the different elements. 
• Groups are the elements having the same outer electron arrangement. The outer electrons are also called the valence electrons.

• Since they have the same number of valence electrons, the elements in a group shares the same chemical properties.
• The Roman numerals listed ABOVE each group are the usual number of valence electrons. 
• These are the groups: IA, IIA, IIIA, IVA, VA, VIA, VIIA, VIIIA

What are Families?

• Groups are also known as Families. The families are the names representing each group. 
• There are 9 different families, and these are the:
• Alkali Metals
• Alkaline Earth Metals
• Transition Metals
• Boron 
• Carbon
• Nitrogen
• Chalcogens
• Halogens
• Noble Gases

What are Periods? 

• Periods are the horizontal rows of elements found in the Periodic Table of Elements. There are 7 periods in the Periodic Table.
• The periods represents the energy level of an atom.

• The number of elements in a period increases as you move downbecause there are more sub levels per level as the energy level of the atom increases.
• According to the table below, not all the periods have the same number of elements.    

Period Number	Number of Elements
1	2
2	8
3	8
4	18
5	18
6	32
7	28

What are Valence?

• Valence is also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element.
• Valence is the number of electrons needed to fill the outermost shell of an atom. 

• For example, when you go across the table from carbon to nitrogen to oxygen, the number of valence electrons increases from 4 to 5 to 6. As we go from fluorine to neon to sodium, the number of valence electrons increases from 7 to 8 and then drops down to 1 when we start the new period.

How to get the element using the periods and groups!

• You can find an element even without the given atomic number just by using the groups and periods. Example: Look for the element that is located on Period 2, Group 4. The element isCarbon because its on the row of period 2 and it is under Group 4.

Try this! Find the element given the period and group number only.

• Period 4, Group 6
• Period 2, Group 2
• Period 5, under the Alkali Metals
• Halogens family, along period 5. 

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Made by: Group 3

Marj Mendoza

Roxy Trillanes

Isabella Meily

Eula Manibog

Djoseth Macomb

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