Name:_______________________
Date:____________ Per #:_____
HW 3.7 – Lewis Structure Practice
Check it out!
Lewis structures become simpler when you notice patterns. Take for example HF:
Hydrogen structure
Fluorine structure
HF structure
Because Cl, Br and I are all in the same group as F (Group 7A), they all have 7 valence electrons, and will have
the same Lewis structure. Subsequently, when they bond with hydrogen, they will all bond the same, and
each molecule will have the same Lewis structure.
HCl structure
HBr structure
HI structure
Instructions: For each molecule given, draw the correct Lewis structure (don’t forget the 3 steps!). Then, identify
2 more molecules with one or more different elements from the same family (like in the example above). Then draw
those Lewis structures (should be the same as the first, but with different letters). For #1, the alternates are given,
but for the rest, you figure it out!
1) CF4 Hint for the alternates: What elements are in carbon’s group? What elements are in
fluorine’s group?
CF4 Lewis Structure
Alternate #1: CBr4
Alternate #2: SiCl4
2) CO2 Hint for the alternates: What elements are in carbon’s group? What elements are in
oxygen’s group?
CO2 Lewis Structure
Alternate #1:
Alternate #2:
Name:_______________________
Date:____________ Per #:_____
3) NH3 Hint for the alternates: What elements are in nitrogen’s group?
NH3 Lewis Structure
Alternate #1:
Alternate #2:
4) H2O Hint for the alternates: What elements are in oxygen’s group?
CO2 Lewis Structure
Alternate #1:
Alternate #2:
5) NOF Hint for the alternates: What elements are in nitrogen’s group? What elements are in
oxygen’s group? What are the elements in fluorine’s group?
NOF Lewis Structure
Alternate #1:
Alternate #2: