Unit 6a Question Packet
Chemical Formulas & Equations
Name …………………KEY………………………
Period ………….
SKILLS
1.
2.
3.
4.
counting ATOMS IN FORMULAS
counting IONS IN IONIC FORMULAS
identifying MOLECULAR & EMPIRICAL FORMULAS
NAMES TO FORMULAS and FORMULAS TO NAMES
SKILL #1:
5. BALANCING EQUATIONS
6. applying the LAW OF CONSERVATION OF MASS
7. identifying TYPES OF REACTIONS
- refer to your notes & RB p. 73 & 87
COUNTING ATOMS IN FORMULAS
1. Fill in the table below. Put an “M” if the substance is molecular/covalent, an “I” if ionic,
and an “H” if a hydrate.
Total
Total
Formula
Moles of each
moles of
Formula
Moles of each
moles of
atom
atoms
atom
atoms
HClO3
CaCl2
1 mol H atoms
1 mol Ca atoms
a.
5
f.
3
1 mol Cl atoms
2 mol Cl atoms
I
I
3 mol O atoms
NH4C2H3O2
b.
I
Mg(OH)2
c.
I
LiCl4H2O
d.
e.
SKILL #2:
H
CH3COOH
I
1 mol N atoms
7 mol H atoms
2 mol C atoms
2 mol O atoms
1 mol Mg atoms
2 mol O atoms
2 mol H atoms
1 mol Li atoms
1 mol Cl atoms
8 mol H atoms
4 mol O atoms
Mg3(PO4)2
12
5
g.
h.
I
CH3CH2CH3
M
Al(SCN)3
14
i.
I
NH4Cl5H2O
2 mol C atoms
4 mol H atoms
2 mol O atoms
8
j.
counting IONS IN IONIC FORMULAS
H
3 mol Mg atoms
2 mol P atoms
8 mol O atoms
13
3 mol C atoms
8 mol H atoms
11
1 mol Al atoms
3 mol S atoms
3 mol C atoms
3 mol N atoms
1 mol N atoms
1 mol Cl atoms
14 mol H atoms
5 mol O atoms
10
21
- refer to your notes, RB p. 73, and Table E!
2. Complete the table below. Use Table E!!!
Ionic
Compound
Cation
(+ ion)
Anion
(- ion)
Total moles
of ions
Ionic
Compound
Cation
(+ ion)
Anion
(- ion)
Total moles
of ions
a.
NH4C2H3O2
NH4+
C2H3O2–
2
e.
CaF2
Ca2+
2 F–
3
b.
Ba(NO3)2
Ba2+
2 NO3–
3
f.
Al2O3
2 Al3+
3 O2–
5
c.
Li2CO3
2 Li+
CO32–
3
g.
KMnO4
K+
MnO4–
2
d.
NaHCO3
Na+
HCO3–
2
h.
(NH4)3PO4
3 NH4+
PO43–
4
SKILL #3:
– refer to your notes & RB p. 74
identifying MOLECULAR & EMPIRICAL FORMULAS
3. Below are a list of formulas. Write the empirical formula (if not already empirical).
SKILL #4:
a. C4H10
C2H5
b. C3H6
CH2
c.
N2O4
e.
C6H10
C3H5
i.
K2S2O3 (ionic)
f.
Al2O3 (ionic)
g.
NH4NO3 (ionic)
h.
C11H22O11 CH2O
j.
S2O4
k.
CH4
l.
C6H12Cl2O2 C3H6ClO
SO2
NO2
d. Na2SO4
(ionic)
– refer to your notes & RB p. 75-78
NAMES TO FORMULAS and FORMULAS TO NAMES
4. Write formulas for the following ionic substances.
Name
sodium
chloride
aluminum
oxide
barium
iodide
gallium
nitride
Formula
NaCl
Al2O3
BaI2
GaN
Name
zinc
sulfide
potassium
fluoride
lithium
bromide
strontium
chloride
Formula
ZnS
KF
LiBr
SrCl2
5. What do the ionic compounds in #4 all have in common? How are they named?
They all contain two elements only.
Metal: always first (element name)
Nonmetal: element root w/ -ide ending
6. Write formulas for the following ionic substances. Use Table E.
Name
sodium
sulfate
aluminum
chromate
magnesium
hydrogen
carbonate
lithium
permanganate
rubidium
oxalate
Formula
Na2SO4
Al2(CrO4)3
Mg(HCO3)2
LiMnO4
Rb2C2O4
Name
barium
phosphate
calcium
hydroxide
potassium
hydrogen
sulfate
ammonium
chloride
sodium
acetate
Formula
Ba3(PO4)2
Ca(OH)2
KHSO4
NH4Cl
NaC2H3O2
7. What do the ionic compounds in #6 all have in common? How are they named?
They all contain polyatomic ions.
+ ion: always first (element name or ammonium)
- ion: second (name on Table E)
8. Write formulas for the following ionic substances. Use Table E if needed.
Name
Formula
lead(II)
iodide
copper(I)
nitrate
iron(III)
sulfate
chromium(V)
chloride
platinum(II)
oxide
Name
Formula
manganese(III)
oxide
copper(II)
nitrate
gold(III)
oxide
titanium(IV)
phosphide
iron(II)
hydroxide
PbI2
CuNO3
Fe2(SO4)3
CrCl5
PtO
Mn2O3
Cu(NO3)2
Au2O3
Ti3P4
Fe(OH)2
9. What do the ionic compounds in #8 all have in common? How are they named?
They all contain metals w/ more than 1 possible charge (oxidation state).
+ ion: always first (element name or ammonium
Charge of metal ion goes as Roman numeral in ( )
- ion: second (name on Table E or root / ide ending)
10. Write IUPAC names the following ionic compounds.
Name
Formula
Name
Formula
lithium bromide
LiBr
lead(II) sulfate
PbSO4
silver oxide
Ag2O
sodium hydrogen carbonate
NaHCO3
barium nitride
Ba3N2
nickel(III) sulfate
Ni2(SO4)3
tin(II) oxide
SnO
titanium(III) oxide
Ti2O3
magnesium nitrate
Mg(NO3)2
aluminum sulfite
Al2(SO3)3
copper(I) phosphide
Cu3P
aluminum cyanide
Al(CN)3
cobalt (III) oxide
Co2O3
ammonium chloride
NH4Cl
silver bromide
AgBr
potassium nitrate
KNO3
sodium nitrate
NaNO3
calcium carbonate
CaCO3
potassium iodide
KI
ammonium carbonate
(NH4)2CO3
sodium hypochlorite
NaClO
sodium thiosulfate
NaS2O3
iron(III) hydroxide
Fe(OH)3
yttrium bromide
YBr3
11. Write formulas for the following molecular substances.
Name
Formula
dinitrogen
trioxide
diphosphorus
pentoxide
sulfur
dioxide
silicon
dioxide
xenon
hexafluoride
tetraphosphorus
decoxide
Name
Formula
silicon
tetrafluoride
carbon
tetrachloride
boron
triiodide
carbon
disulfide
phosphorus
pentabromide
boron
trihydride
N2O3
P2O5
SO2
SiO2
XeF6
P4O10
SiF4
CCl4
BI3
CS2
PBr5
BH3
12. Write IUPAC names for the following molecular substances.
Name
Formula
Name
Formula
dinitrogen pentoxide
N2O5
dihydrogen monosulfide
H2S
sulfur hexafluoride
SF6
boron trifluoride
BF3
phosphorus tribromide
PBr3
phosphorus trihydride
PH3
sulfur trioxide
SO3
dihydrogen monoxide (water)
H2O
diboron tetrahydride
B2H4
chlorine
Cl2
SKILL #5:
– refer to your notes & RB p. 79, 81
BALANCING EQUATIONS
13. Balance the following equations using the smallest, whole-number coefficients.
a.
__3__Mg
*Start w/ O
+
____Mn2O3

__3__MgO
+
__2__Mn
b.
_____C6H12O6  ___2__C2H5OH + ___2__CO2
*Start w/ H
c.
_____C3H8 +
__5__ O2
 __4__ H2O
+ __3__ CO2
*start w/ C or H
d.
__2__FeCl3 + ____Be3(PO4)2
*Start w/ Be, Cl, or (PO4)

__3__BeCl2
+
__2__FePO4
e.
__4__NH3 +
*Start w/ H
__3__O2

__2__N2 +
__6__H2O
f.
__3__ C2H4O2 + ____ PCl3  __3__ C2H3OCl + ____ H3PO3
*start w/ Cl
*g.
_____Fe2O3 + __3___CO  __2__Fe + __3__CO2
* must start w/ O, want an EVEN # of O’s on both sides, so CO
gets a 3 in front
SKILL #6:
– refer to your notes & RB p. 81
applying the LAW OF CONSERVATION OF MASS
14. Given the reaction:
2H2 + O2  2H2O
What is the total mass of water formed when 8 grams of hydrogen reacts completely
with 64 grams of oxygen?
8 g + 64 g = X
72 g = X
15. When glucose is fermented, it produces ethanol and carbon dioxide. If 60.0 grams of
glucose is fermented and produces 16.5 grams of carbon dioxide gas, what mass of
ethanol is produced?
Glucose  ethanol + CO2
60 g =
X + 16.5 g
43.5 g =
X
16. A 4.86-gram sample of calcium reacted completely with oxygen to form 6.80 grams of
calcium oxide. This reaction is represented by the balanced equation below.
2Ca(s) + O2(g)  2CaO(s)
Determine the total mass of oxygen that reacted.
4.86 g + X
= 6.80 g
X
= 1.94 g
17. Given the following incomplete equations, write the formula of the molecule represented
by X.
a.
X + Cl2  C2H5Cl + HCl
C2H6
b.
4Fe + 3O2  2X
Fe2O3
18. Which equation represents conservation of mass?
(1) H2 + Cl2  HCl
(2) H2 + Cl2 2HCl
(3) H2 + O2  H2O
SKILL # 7:
(4) H2 + O2  2H2O
– refer to your notes & RB p. 80
identifying TYPES OF REACTIONS
19. Complete the table below.
Equation
Reactant(s)
Product(s)
Type of Reaction
a.
Cl2 + 2NaI  2NaCl + I2
Cl2 + NaI
NaCl + I2
Single replacement
b.
HNO3 + LiOH  H2O + LiNO3
HNO3 + LiOH
H2O + LiNO3
Double replacement
c.
2NaN3  2Na + 3N2
NaN3
Na + N2
decomposition
d.
Ba(NO3)2 + K2SO4 
2KNO3 + BaSO4
Ba(NO3)2 +
K2SO4
KNO3 + BaSO4
Double replacement
e.
BaO + SO3  BaSO4
BaO + SO3
BaSO4
synthesis
f.
2Al + Fe2O3  Al2O3 + 2Fe
Al + Fe2O3
Al2O3 + Fe
Single replacement
g.
P4 + 6Cl2  4PCl3
P4 + Cl2
PCl3
synthesis