1. Covalent Bonds
Electrons are shared

2. How do you identify a covalent formula?
All Nonmetals in formula
How do you identify a covalent formula?

3. Another name for a covalent compound
Molecular compound

4. To get the configuration of a noble gas
Why do atoms form bonds?

5. Linear
Shape of all diatomics?

6. Pyramid
Shape of NH3, NF3, PH3, etc?

7. Bent
Shape of H2O, H2S, H2Se, etc.?

8. How do you make a Lewis Dot Structure?
Arrange the symbols
Count up the valence electrons
Distribute the valence electrons, starting with the bonding pairs – single bonds
Tests
How do you make a Lewis Dot Structure?

9. :N:::N: H :
H:C:H :   H
:O::O: :  
:Cl:
:O::C::O: : : :
:Cl:C:Cl:  : : :
H:F:
:Cl:  :

10. Tetrahedral
Shape of CH4, CCl4, etc.?

11. Has poles – the ends are different!
Polar

12. Electron cloud is NOT symmetric. Separation of charge.
Polar

13. Electronegativity Difference is 0.5 to 1.7
Polar

14. No poles. Ends are the same.
Nonpolar

15. Electron cloud is symmetric. No separation of charge.
Nonpolar

16. Even, balanced.
Symmetrical

17. Electronegativity difference = 0 to 0.5
Nonpolar

18. Electronegativity difference  1.7
Ionic

19. Extremely polar
Ionic

20. Formula has a metal and a nonmetal
Ionic

21. Polar. Water is bent. The O end is a bit negative & the H end is a bit positive.

22. Results from attractions between nucleus on 1 atom & electrons on another atom.
Bonding

23. releases energy - exothermic
Making a bond …

24. Absorbs energy - endothermic
Breaking a bond …

25. Covalent Compounds are
Molecular compounds.
Covalent Compounds are

26. Triple Bond N2

27. Double Bond O2

28. When bonds are made, energy is …
released.
When bonds are made, energy is …

29. When bonds are broken, energy is …
absorbed.
When bonds are broken, energy is …

30. If something exists, it is stable.
Stability

31. As the energy of a system , the stability generally …
increases.
As the energy of a system , the stability generally …

32. As the energy of a system , the stability generally …
decreases.
As the energy of a system , the stability generally …

33. System releases energy. Its energy level goes down.
Exothermic

34. Properties of Molecular Substances
Soft
Low melting point & low boiling point
Does not conduct electricity in any phase
Does not dissolve in water
React slowly
Properties of Molecular Substances

35. Electrons are shared equally between the two atoms
Nonpolar Bonds

36. Molecule must contain polar bonds and they must be arranged asymmetrically.
Molecular Polarity

37. Molecular Polarity Depends on the shape (Bent & Pyramidal are polar
Linear & tetrahedral, polarity depends on composition.)
Molecular Polarity

38. Nonpolar Molecules Noble gas atoms (kickballs)
Diatomics of the form A2 (footballs)
Larger molecules that have high symmetry
Nonpolar Molecules

39. Diatomics of the form AB Larger molecules that have low symmetry
Polar Molecules

40. Nonpolar Molecules Weak Intermolecular Forces
(Dispersion or Van der Waals)
Low boiling points & melting points
Tend to be gases
Nonpolar Molecules

41. Polar Molecules Intermolecular Forces are Dipole-dipole forces
Stick together easier than nonpolar molecules
Polar Molecules

42. Coordinate Covalent Bond
Covalent bond where both electrons in the bond are donated by 1 atom.
Coordinate Covalent Bond

43. Coordinate Covalent Bond+ H
H:N:H
H:N:H H .. ..
+ H+  .. ..
Coordinate Covalent Bond

44. Coordinate Covalent Bond
Both electrons in the bond are donated by the same atom.
Coordinate Covalent Bond

45. Compound that exhibits both covalent & ionic bonding
Compound that contains a polyatomic ion.
Compound that exhibits both covalent & ionic bonding

46. How to calculate the polarity of a bond
Subtract the electronegativities of the 2 atoms.
How to calculate the polarity of a bond

47. Van der Waals forces Or dispersion forces.
Occur between nonpolar molecules.
Weakest intermolecular force.
Strength increases with size of molecule.
Van der Waals forces

48. Occurs between polar molecules. Intermediate intermolecular force.
Dipole-dipole forces

49. Occurs between molecules containing H-F, H-O, or H-N bonds.
Strongest intermolecular force.
Leads to unusually high boiling points.
Hydrogen Bonding