Question 1 of 20
saplin;!iearning
Complete the Lewis structures of the atoms and ions by adding electrons, as needed.
b) Na
a) Li
~
E:J
c) Na+
E:j
Question 2 of 20
saplin;rtarning
Add electron dots and charges as necessary to show the reaction of calcium and oxygen to form an ionic
compound .
Neutral atoms
~
+
9
~
+
+
~
a
~
+
Ions
1
~
0
~
+
Ga
~
,
~
,
~
+
~
0
I~-
+
tj t
Question 3 of 20
saplin;fiearning
Complete these structures by adding dots as needed.
F-H
+
T TTITI TnT T TTl
You can clear your work by
clicking the button that looks
like two red arrows.
I
Question 4 of 20
saplin@earning
Draw the Lewis structure of the following molecule. Include lone pairs, if necessary.
H-
--
- !---L '--1-1
-
1-'
S
H
+
~
+
-
~
+
~
+
-
~
+
~
+
-
~
+
~
+
~
+
~
+
1
1
-II
1
t
-
+
~
~
Question 5 of 20
saplin~arning
Draw Lewis structures for the following molecules. Include all lone pairs of electrons in your drawing.
a) Some elements, such as hydrogen , beryllium, and boron have too few valence electrons to form
an octet. Draw the Lewis structure for beryllium fluoride, BeF2.
~
+
+
~
+
~
+
+
~
+
+
+
~
+
+
I
b) Some elements in the third period and later in the periodic table can expand beyond an octet of
electrons . Draw the Lewis structure for AsFs.
I
f-
~
+
I I
+
~
+
+
~
+
+
~
+
Question 6 of 20
saplin~aming
How many single, double, and triple bonds are in this molecule?
Number
~
single bond(s)
Number
~
double
bond(s)
Number
~
triple
bond(s)
Question 7 of 20
saplin~arning
Click on the green bonds to change them to double or triple bonds as needed.
If the bond is already correct, you do not need to do anything to that bond.
H - G -C-H
+-
You can clear your work by
clicking the button that looks
like two red arrows.
Make sure you only alter the
green bond in each structure.
Do not add any dots . Do not
change the H atoms or the
black bonds in any way.
Question 8 of 20
saplin;{iearning
Formaldehyde, CH 20, is used as an embalming agent. Draw the structure of CH 2 0 including lone pairs.
+
+-
+
+-
+
+
+-
+
+-
+
+
+-
+
+-
+
+
+-
+
+-
+
+
+-
+
+-
+
+
+-
+
+-
+
Drawing tips:
1. Click once on the grid, then just start drawing (click, hold, and drag).
2. Double-click on a letter then type to change the atom label.
3. Click on a bond to cycle through single, double, and triple .
4. Use the lone-pair button to add lone pairs.
Note: after using the lone pair button, you will need to click on the
bond button if you want to edit the bonds or atoms again.
Question 9 of 20
saplin~earning
Draw the Lewis structure of the following molecule. Include lone pairs.
HCN
-~~~+-+-+-+-+-+-+-~
-~-+-r~+-~~-+-H
Question 10 of 20
saplin~arning
Select the true statements regarding these resonance structures of formate.
:0..~..0
!
o
..O·,
. .~
!
Each carbon-oyxgen bond is somewhere between a single and double bond.
The actual structure of formate is an average of the two resonance forms.
:
The actual structure of formate switches back and forth between the two resonance forms.
Each oxygen atom has a double bond 50% of the time.
:
Question 11 of 20
saplin#.arning
Which of these molecules and polyatomic ions cannot be adequately described using a single Lewis
structure? Check all that apply.
I
col-
I
COH 2
I
HCN
I
NH/
I
03
I
OF2
Question 12 of 20
saplin~arning
Draw an appropriate Lewis structure for ozone , 0 3. Include lone-pair electrons.
-
~ 1--
~
l-
I-
ee-
+
-
-
+
r--
+
-I-
I-
~
+
t-
-
Number
~
How many total resonance forms does the ozone molecule have?
Question 13 of 20
Predict the molecular shape of methane, the carbonate ion , carbon dioxide, and the sulfite ion .
Methane, CH 4:
0
0
0
0
0
H
J-H
I
H
Carbonate ion ,
coi-:
:9~:
°0
0
°
Carbon dioxide, COi
bent
trigonal pyramidal
R=R
tetrahedral
trigonal planar (120°)
linear
o
o
o
o
o
Sulfite ion,
bent
trigonal pyramidal
tetrahedral
soi-:
:~s=ci:
.. ·6· .
trigonal planar (120°)
linear
0
0
0
0
0
o
o
o
o
o
bent
trigonal pyramidal
tetrahedral
trigonal planar (120°)
linear
bent
trigonal pyramidal
tetrahedral
trigonal planar (120°)
linear
Question 14 of 20
•
Donald Mcquarrie· Peter A Rock· Ethan Gallogly '"
• • '-L) Umverslty SCience Book
_
nil presented by Saplmg le
Compare the shapes and bond angles of these oxynitrogen ions.
Linear
180°
Question 15 of 20
saplin~aming
Trigonal planar
120°
Tetrahedral
109.5°
Bent
" 120°
Bent
" 109°
Pyramidal
" 109°
Rank these elements according to electronegativity.
Most electronegative
Least electronegative
CKFGaRb
Question 16 of 20
saplin#.arning
Classify these bonds as ionic, polar covalent, or nonpolar covalent.
Ionic
Polar covalent
Nonpolar covalent
Jl
Na-F
C-C
J
S-O
Question 17 of 20
saplin@earning
Select the polar bonds in the compounds below. Select only bonds. A selected bond will turn green.
a)
H
CI-!-H
!
c)
H
I ..
H-C--N--H
! !
Question 18 of 20
saplin;iiearning
For each molecule below, specify the polarity of the bonds and the overall polarity of the molecule.
:(::)-B-9):
H-R-H
bonds
bonds
molecule
molecule
.-..rF:.\.
Question 19 of 20
Organic Chemistry
~ ~
Ma rc Loudon
Robert s & Company Pubhshe
prasented by Saphng Leammg
Draw a Lewis structure for H30+. Show all unshared pairs and the formal charges, if any.
Assume that bonding follows the octet rule.
+
+-
+
Question 20 of 20
saplin;fiearning
Draw the Lewis structure for ammonium, NH/. Include formal charges.
I I
~
I I
~
+
~
+-
f-
~
+
~
+-
t
-
~
~
~
+
-
~
+
~
-II
~
~
+ +-
,I
f-