11-11 Gen Chem - Bellwork
 Write
 In
the formula for
complete sentences compare
and contrast covalent and ionic
bonding (at 1 similarity and 2
differences)
Name ‘em!
SO2
SO3
N2O
NO
PF5
Sulfur dioxide
Sulfur trioxide
Dinitrogen monoxide
Nitrogen monoxide
Phosphorous pentafluoride
SCl6 Sulfur hexachloride
P2O5 Diphosphorous pentoxide
H2O
Dihydrogen monoxide
 Write
1.
2.
3.
4.
5.
the formula
Trinitrogen tetraphosphide
Carbon monoxide
Copper (II) Oxide
Calcium Carbonate
Phosphorus trihydride
 Shows
e-
element symbols, bonds and valence
Step 1
Count total valence e- for the
total molecule
Ex. PCl3
P=5
Cl=7x3=21
Total= 26

Count up the total valence e- for
each molecule
 H2O (1x2) + 6= 8
 H2 1x2= 2
 Hydrochloric acid HCl= 1+7= 8
 Nitrogen
trihydride
NH3=5+ (1x3)= 8
Step 2: Put lone atom in center
and others around it. Give them
each single bonds.
Cl
P
Cl
Cl
*Single bonds contain 2 shared electrons!
Put
the lone atom in the
center and add single bonds
 H2O
 H2
 Hydrochloric
acid
 Nitrogen trihydride
Step
3: Fill the outside atoms
with octets
Cl
P
Cl
Cl
Step 4: Count how many eyou’ve used. Any leftovers, add to
central atom
Cl
P
Cl
Cl
Step 5: If the center has octet or
more, you’re good!
If not, borrow pairs from outside
and make double and triple bonds
Cl
P
Cl
Cl
CO2
1.
2.
C=4, O=6x2=12, Total e-=16
O
C
O
3. Count used e- (16 so far, none left!)
C doesn’t have an octet!!
O
C
O
If the center has octet or more,
you’re good! If not, borrow pairs from
outside and make double and triple
bonds
4.
O
O
C
C
O
O
1.
2.
3.
4.
5.
6.
7.
8.
PH3
PCl3
H 2S
OF2
NF3
CO
N2
O2
*You can have more than an
octet on the center!
Why?! Think about orbitals…
P is 3s23p3
But…it can actually fit more e- in the
3d orbitals! (3rd energy level!)
1.
2.
3.
4.
SF6
ClF3
BrF5
XeF4
 Quick
write
 What
is the main difference
between ionic and covalent bonds?