2. Example: Se Se

3. 1s22s22p63s23p64s23d104p4 = [Ar] 4s23d104p4
Example: Se Se

4. Clicker #1
How many unpaired electrons and valence electrons does Se have?
A) 0; 14
B) 2; 6
C) 2; 14
D) 0; 6
E) 2; 4

5. Atomic Trends H F Fr Atomic Radius: size of the orbital decreasing
increasing Fr

6. Atomic Trends H F Fr Atomic Radius: size of the orbital decreasing
More protons = more attraction and smaller radius
Orbitals are getting bigger and further from nucleus
increasing Fr

7. Clicker #2
Which of the following elements has the largest atomic radius?
A) Ca
B) Al
C) N
D) Sr
E) F

8. Atomic Trends
Ionization Energy
increasing H F
decreasing Fr

9. Atomic Trends H F Fr Ionization Energy increasing decreasing
Electron is at its lowest energy state when closest to the nucleus
takes more energy to take an electron away when closer to the nucleus
decreasing Fr

10. Clicker #3
Which of the following elements has the largest ionization energy?
A) P
B) Al
C) Cl
D) Ba
E) K

11. Isoelectronic Series Same number of electrons Example:
Which is larger Na+ or Ne?

12. Isoelectronic Series Same number of electrons Example:
Which is larger Na+ or Ne?
Same number of electrons but Na+ has 11 protons and Ne has 10 protons.

13. Example Which is larger Cl- or Ar?
Which has a higher ionization energy Cl- or Ar?

14. Example Which is larger Cl- or Ar?
Which has a higher ionization energy Cl- or Ar?

15. BONDING “Forces” What is meant by a “chemical bond”?
Why do atoms bond to form molecules?
How do atoms bond to form molecules?

16. BONDING Two Types of Bonding Intramolecular (within a molecule)
Intermolecular (between molecules)

17. Ionic Compounds Between a metal and a nonmetal Example: NaCl
Na: [Ne]3s1
Cl: [Ne]3s23p5

18. Ionic Compounds Between a metal and a nonmetal Example: NaCl
Na: [Ne]3s Na+: [Ne]
Cl: [Ne]3s23p Cl-: [Ne] 3s23p6

19. Mg -> Mg+ -> Mg2+ OVERALL = EXOTHERMIC PROCESS
Ionization energies of atoms are highly endothermic
HOWEVER…
Takes more energy to remove 2nd electron
Once you get Mg2+ (noble gas configuration) gives off energy
OVERALL = EXOTHERMIC PROCESS

20. Bonding in H2
Is this ionic?

21. Bonding in H2 Covalent Bonding Sharing electrons
Hydrogens share the electrons and have noble gas configuration
Why isn’t He diatomic?

22. Bonding in H2 Covalent Bonding Sharing electrons
Hydrogens share the electrons and have noble gas configuration
Why isn’t He diatomic?
Already has a noble gas configuration

23. Therefore… Covalent bonding has same idea as ionic bonding… But
Neither atom is “strong” enough to remove electron from the other atom

24. What about CO?