1. Ionic and Covalent Bonds

2. Ion Ion: atom or group of atoms with an electrical charge (+) or (-)
Atom loses an electron  loses a negative charge and becomes more positive
Atom gains an electron  gains a negative charge and becomes more negative
Polyatomic Ions: Ions that are made up of more than one atom
Phosphate PO4 ^3-
Nitrate NO3-

3. Fill in the Blank
An ion is an atom with an ___________________ charge. (+) or (-)
When an atom loses an electron it becomes more _________
When an atom gains an electron it become more _____________
Electric, positive, negative

4. Ionic Bonds
When these two types of atoms combine, electrons are transferred from one type of atom to the other  Both atoms are more stable
Ionic Bonds form as a result of the attraction between positive and negative ions
Usually occur between metals and nonmetals
Atoms with 5, 6, and 7 valence electrons want 8  More stable
Atoms with 1, 2, 3, want to lose their valence electrons  More stable

5. Fill in the Blank
An Ionic bond is when an atom ____________ its ____________ to another atom
Ionic Bonds form as a result of the attraction between ______________ & ________________ ions
Ionic bonds occur between _______________ & ________________
Transfers, electrons, positive and negative, metals & nonetals

6. Properties of Ionic Compounds
Hard
Brittle
High melting points
When dissolved or melted  conduct electricity
Form between metal and nonmetal
Ionic bonds are strong, a lot of energy is required to break them  high melting point
When dissolved, the bonds are broken leaving electricity to flow through
Ionic compounds in solids do not conduct current well

7. Covalent Bonds Atoms share electrons Usually form between nonmetals
With the exception of the noble gases, nonmetals bond with other nonmetals by sharing electrons

8. Fill in the blank
Covalent bond occurs when atoms _____________ electrons
Covalent bond form between ________________
Dogs explain chemical bonds
Share, nonmetals

9. Chemical Formulas and Names
Chemical Formula: Combination of symbols that show the ratio of elements in a compound
Ex. MgCl2 What does this formula tell you?
1 Magnesium and 2 Chlorides
Ex. CaCO3
1 Calcium 1 Carbon 3 Oxygen
Ex. H2O

10. Drawing Lewis Dot Structures
=1ZlnzyHahvo
1. Find number of valence electrons
2. Put the least electronegative atom in center
3. Place two electron in between atoms to form bonds
4. Compete octets
5. Move electrons to form double/triple bonds

11. Double Bonds and Triple Bonds
Double bond: atoms share two pairs of electrons
Triple Bonds: atoms share three pairs of electrons

12. Molecular Compound Molecular compounds are covalently bonded
Different properties than Ionic compounds
Lower melting/boiling points
Do not conduct electricity when dissolved

13. Unequal sharing of electrons in Covalent Bonds
Some atoms pull more strongly on electrons than other atoms
This causes the atoms to have a slight electrical charge
Charges are not as strong as ions
Atom with the stronger pull = slightly negative
Atom with weaker pull =slightly positive
THIS UNEQUAL SHARING IS CALLED POLAR
Equally shared electrons between atoms is called nonpolar

14. Fill in the blank
Atom with the stronger pull have a slightly _____________ charge
Atom with weaker pull have a slightly _____________ charge
Unequal sharing of electrons are called a ________________ bond
Negative, positive, polar