More to Know about the

Periodic Table!You know you love notes

REVIEW:

• Periods are horizontal (across) rows of elements on the periodic table. A row is called a period because the properties in a row follow a repeating, or periodic pattern as you move across each period. Periods are numbered 1-7.

• Groups or Families are vertical (up and down) columns and are called families because they share similar characteristics similar to our families.

All in the Family…

• Group 1: Alkali Metals• Group 2: Alkaline Earth

Metals• Groups 3-12: Transition Metals• Group 13: Boron Group• Group 14: Carbon Group• Group 15: Nitrogen Group• Group 16: Oxygen Group• Group 17: Halogens• Group 18: Noble Gases

Electron Cloud Configuration – Energy

Levels• Although all the electrons in an

atom are somewhere in the electron cloud, some electrons are closer to the nucleus than others.

• The different areas for an electron in an atom are called energy levels.

• The closer an energy level is from the nucleus, the fewer electrons it can hold.

• The farther an energy level is from the nucleus, the more electrons it can hold.

• Electron locations generally start from the inner most energy level and work outward.

E.C.C. – Distance

• 1st energy level (closest to the nucleus) = up to 2 Es– Period 1 elements have 1 energy level

• 2nd energy level = up to 8 Es– Period 2 elements have 2 energy levels

• 3rd energy level = up to 18 Es; HOWEVER, we will consider 8 Es to be FULL – Period 3 elements have 3 energy levels

• 4th energy level = up to 32 Es; HOWEVER, we will consider 8 Es to be FULL– Period 4 elements have 4 energy levels

SKIP TRANSITION METALS (groups 3-12)

E.C.C. – Quantity

• Starting at the 3rd energy level,

electron configurations change

slightly due to the characteristics of

transition metals

• Since this is introductory chemistry,

we will not explore the electron

configurations of transition metals

or of elements beyond period 4.

E.C.C. – EXCEPTIONS

• Farther an electron is away from nucleus:– more energy

available– easier to remove

• Closer an electron is to nucleus:– less energy

available– harder to

remove

E.C.C. – amounts of energy

• The energy level also relates to the amount of energy electrons have within the atom.

• Electrons farthest from the nucleus have the highest amount of energy and are the easiest to remove.

• Electrons closest to the nucleus have the lowest amount of energy and are more difficult to remove because the closer a negatively charged electron is to the positively charged nucleus, the more strongly it is attracted to the nucleus

• Thus, removing electrons closest to the nucleus takes more energy than removing those that are farther away

E.C.C. – amounts of energy

Valence Electrons• The electrons in the outermost energy

level of an atom are called valence electrons.

• The valence electrons determine whether an atom will form bonds.

• An atoms with a full outer energy level will not usually form bonds

• For example, the noble gases in group 18 are happy and therefore do not usually form bonds.

Valence Electrons

• The group number for of groups 1 and 2 indicate the amount of valence electrons

• The group number minus 10 for groups 13-18 indicates the number of valence electrons.

• How many valence electrons?

Valence Electrons

• How many valence electrons?

• What Group?

Valence Electrons

• How many valence electrons?

• What Group?

Quote of the Day:

“Equipped with his five senses, man explores the universe around him and

calls the adventure Science.” 

~Edwin Powell Hubble, The Nature of Science, 1954

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