Name: _______________ANSWER KEY___________________ Date: ___________________________ Period: ________
Interpreting & Understanding Lewis Structures
Covalent bonding in the hydrogen molecule, H2
Energy Level Diagrams
Lewis Dot Diagrams
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What do the pair of dots between the two letters “H” represent? 2 electrons
-
What does the line between the two letters “H” represent? A bond
Covalent bonding in the water molecule, H2O (Water)
Energy Level Diagrams
Lewis Dot Diagrams
Water has two hydrogen atoms covalently bonded to an oxygen atom. Methane has four hydrogen
atoms covalently bonded to a carbon atom.
-
Draw Lewis diagrams for methane (CH4) using dots for pairs of electrons and then lines for
pairs of electrons.
Ionic bonding of sodium chloride, NaCl
- In the second dot diagram, why are
there no electrons surrounding
sodium?
Because it gave its electron away
- In the final dot diagram of NaCl, the
dots between the sodium and
chlorine are between the atoms. Are
these atoms sharing the electrons?
No, chlorine has them all
Lewis Structure Practice
Guidelines:
1. The octet rule says that atoms “try” to have 8 valence electrons by sharing or transferring
electrons to form compounds. *Hydrogen and Helium only have 2 electrons in their “octet”
2. Determine the number of valence electrons
3. Put the atom which can share the most electrons in the middle (think about their individual
dot diagrams)
4. Determine and bond the terminal atoms.
5. Remember: Some atoms can share two or three pairs of electrons (usually it is C, N, or O)
6. Hydrogen and fluorine NEVER share two pairs of electrons.
HF
CH4
PH3
N2
C2Cl6
O2
BF3
NH4+
NO3-