1. ATOMSATOMS*

2. HistoryHistory*of the Atom  Many ancient Indian/Greek philosophers had ideas about tiny particles  1661 Robert Boyle “matter is composed of various combinations of atoms instead of the 4 classical elements.” (Earth, Wind, Fire, Water.)

3. Atoms- General info  All matter is made up of atoms  Atoms cannot be divided or broken down using chemicals  Atoms are very small.

4. Atoms- General Info cont.  Most of the mass of an atom is made up of the nucleus (protons/neutrons)  Most of the volume of an atom is made up through the electrons.  Atoms are held together by very strong forces called bonds.

5. StructureStructure* of the Atom  Protons/Neutrons- larger than electrons  Protons (+) charge  Neutrons (0 neutral) charge  Electrons (-) charge  Electrons orbit around the nucleus of the atom

6. Atomic Number  Atomic Number is the element # and is also the # of protons.

7. Ions and Isotopes  If the number of electrons changes in an element it is an ion.  Ions and Isotopes are the various forms than an element can come in.

8. Ions and Isotopes  If the number of neutrons changes it is called an isotope.  Carbon is an element that comes in many forms http://www.youtube.com/watch?v=GsJPxR6IfZI

9. Radioactive isotopes  Some isotopes lose neutrons making them “unstable.”  As these isotopes lost neutrons they give off energy in the form of radioactivity. http://www.youtube.com/watch?v=cKJMk2Oio d0

10. *THE MODERN PERIODIC TABLE Obj: Students will be able to explain the three classifications of elements and the approximate number of them on the Periodic Table.

11. Periodic Table

12. The Modern Periodic Table  Arranged by increasing atomic # (# of protons)  Also arranged by number of available orbitals per energy level (rows)-periods.  *Mendeleev was not aware that elements have different numbers of protons.  www.ptable.com www.ptable.com

13. Periods/Rows  Organized by energy levels available.  Lightest--  Heaviest elements (atomic mass)

14. Groups/Families  Each column on the periodic table  Elements in a group all have similar properties  Properties of elements repeat predictably when atomic number is used to arrange groups (periodic law)  Similar electron configurations  All have the same number of valence e-

15. Assignment  Complete the table below using a periodic table for elements # 1-10 Element nameSymbolAtomic #/# of Protons Atomic Mass # of neutrons (atomic mass (rounded- atomic #) # of electrons HydrogenH11.0001

16. *Beautiful Elements

17. Available Orbitals Energy Level Electrons 12 28 318 432

18. Valence Electrons  Valence electrons are the electrons that are in the outermost energy level of an atom  The number of valence electrons an element has will determine how an element chemically will bond with other elements  www.ptable.com www.ptable.com

19. Assign  Practice chemical bonding and identifying valence electrons.  You will need 2 different colors.

20. Compounds  Substance formed chemically by two or more elements.

21. *CHEMICAL BONDS Forces that holds atoms or ions together.

22. Electron Configurations  It all goes back to the periodic table…  1. Valence electrons determine how an element will bond with other elements.  a. highest energy level of an atom either gains or loses electron.

23. Electron Configurations -b. elements are trying to achieve stable 8 configuration by gaining or losing electrons  c. groups 1,2,13,14 all lose an electron, groups 14-17 all gain electrons.

24. *Formation of Ions  Formation of Ions  a. elements that do not have 8 valence electrons react easily.  b. reaction and bonding allows the elements to achieve stable electron configurations.  c. when an atom gains or loses an electron the number of protons/electrons is no longer equal. i. atoms that are positive or negative are called ions and are represented by a positive or negative sign (-) or (+)  e. negative charge is called an anion  f. positive charge is called a cation

25. Ionic Bonds- Electron Transfer  Ionic Bond (remember that positive and negative particles attract each other)  a. when cations and anions are in close proximity a chemical bond forms between the two atoms.  b. an ionic bond is a force that holds cations and anions together.  c. forms when electrons are transferred between atoms. http://vimeo.com/7822850

26. *Covalent Bonds- *Covalent Bonds- Shared Electrons  Covalent Bond  A chemical bond in which two atoms share a pair of valence electrons.  a single bond is a bond in which two atoms share one pair of electrons.  attraction of shared electrons and protons in each nucleus hold atoms together in covalent bonds.  Forms between atoms that are non-metals

27. Bonding

28. Assign Chemical bonding cartoon (due Monday)

29. Chemical bonding  Ionic bonding- electrons are lost/gained (transferred) to other atoms. When an atom is lost it receives a positive + charge and is called a cation. When an atom is gained it receives a negative charge – and is called an anion.  Covalent bonding- electrons are shared with other atoms