Name: _________________ ws#:____
Guess that Molecule!
Name:
_______________Blk:____
Science/Phipps/Block
# _____
Directions: Use the key to determine the chemical formula for each molecule model that is shown in class.
Write the number of atoms that the molecule contains as a subscript. An example is shown. Hint: the
chemical name sometimes gives a clue as to what order the atoms are listed in the chemical formula.
(Small) PurpleHydrogen (H)
Light PurpleSodium (Na)
Station #
Example
1
2
3
4
5
6
BlueNitrogen (N)
GreenChlorine (Cl)
# and color of balls
6 Black
12 Purple
6 Red
BlackCarbon (C)
Pink- Magnesium
(Mg)
RedOxygen (0)

Molecule
Name of Molecule
C12H22O11
Table Sugar
Identifying the elements in various compounds
Directions: On each line write the name of the elements that are denoted in each of the chemical formulas. Then in the
parenthesis, write the number of atoms that can be found in the molecule. Remember, each chemical element begins
with a capital letter.
The subscript (number below) tells us the number of atoms of a certain element.
Example:
Fe3O4 = There are three Iron (Fe) atoms and four oxygen atoms. The subscript is
always written after the element it applies to and it doesn’t apply to any other elements.
Fe3O4 = Iron____________ ( 3 )
Oxygen__________( 4 )
1.
Water =H2O = _______________ (
)
2.
Salt =NaCl
3.
NH4
4.
AgNO3 =_____________ (
5.
NH4Cl =_____________ (
)_____________ (
)_______________ (
)
6.
CoCO3=_____________ (
)_____________ (
)_______________ (
)
7.
Sugar = C12H22O11 =_____________ (
=_______________ (
=_______________ (
_______________ (
) _______________ (
) _______________ (
)_____________ (
)
)
)
)_______________ (
)_____________ (
)
)__________ (
)
Now, the coefficient in front of the molecule tells us how many molecules of that compound
are present (ex. 2H2O is two water molecules). Therefore, each coefficient is multiplied by
each subscript. If there is no subscript written, then it is automatically one.
8.
5H2O =_______________ (
) _______________ (
9.
Carbon Dioxide 4CO2 = _______________ (
10.
3NaCl
=_______________ (
11.
4SO4 =
_______________ (
12.
3Na2SO4 = =_____________ (
)
)
), _______________ (
) _______________ (
)
_______________ (
)
)_____________ (
)
)_______________ (
)
13. To the left of each problem above, write the total number of atoms found in each element.
14. Place a box around every coefficient above, and a circle around each subscript.
Guess that Molecule!
Name: KEY
Blk:____
Directions: Use the key to determine the chemical formula for each molecule model that is shown in class.
Write the number of atoms that the molecule contains as a subscript. An example is shown. Hint: the
chemical name sometimes gives a clue as to what order the atoms are listed in the chemical formula.
(Small) PurpleHydrogen (H)
Light PurpleSodium (Na)
Station #
Example
BlueNitrogen (N)
GreenChlorine (Cl)
# and color of balls
12 Black
22 Purple
11 Red
BlackCarbon (C)
Pink- Magnesium
(Mg)
RedOxygen (0)
XXX
Molecule
Name of Molecule
C12H22O11
Table Sugar
2 green
Cl2
Chlorine
2 purple
H2
Hydrogen
2 Red
O2
Oxygen
1A
2A
3A
2 Blue
4A
N2
Nitrogen
HCl
Hydrogen Chloride
5A
1 Green
1 Purple
NaCl
Sodium Chloride (Salt)
6A
1 Green
1 Light Purple
1B
1 Pink
2 Green
2B
1 Black
2 Red
3B
2 Red
2 Purple
4B
1 Blue
3 Purple
5B
2 Hydrogen
1 Red
6B
1 Black
4 Purple
7B
2 Black
6 Purple
8B
2 Black
4 Purple
9B
2 Black
2 Purple
10 B
3 Black
8 Purple
MgCl2
Magnesium Chloride
CO2
Carbon Dioxide
H2O2
Hydrogen Peroxide
NH3
Ammonia
H2O
Water
(Dihydrogen Monoxide)
CH4
Methane
C2H6
Ethane
C2H4
Ethylene (Ethene)
C2H2
Acetylene (Ethyne)
C3H8
Propane