Tuesday Oct 9 homework answers.notebook
October 09, 2012
Remember...
http://www.youtube.com/watch?v=tE4668aarck
Mar 5­11:53 AM
Homework
p. 239
#1. a) zinc chloride --> zinc + chlorine decomposition
b) potassium + iodide --> potassium iodide synthesis
c) potassium oxide + water --> potassium hydroxide
synthesis
d) calcium carbonate --> calcium oxide + carbon dioxide decomposition
#2. a) ZnCl2 --> Zn + Cl2 already balanced!
b) 2K + I2 --> 2KI
c) K2O + H2O --> KOH K2O + H2O --> 2 KOH
d) CaCO3 --> CaO + CO2 already balanced!
p. 242
#3.
a) aluminum + iron(III)oxide --> aluminum oxide + iron
single displacement
b) barium chloride + sodium sulfate --> barium sulfate + sodium chloride double displacement
c) zinc + copper(II) sulfate --> zinc sulfate + copper
single displacement
d) silver nitrate + sodium phosphate --> silver phosphate + sodium nitrate double displacement
e) calcium + water --> hydrogen + calcium hydroxide
single displacement
4.
a) Al + Fe2O3 --> Al2O3 + Fe 2Al + Fe2O3 --> Al2O3 + 2Fe
b) BaCl2 + Na2SO4 --> BaSO4 + NaCl
BaCl2 + Na2SO4 --> BaSO4 + 2NaCl
c) Zn + CuSO4 --> ZnSO4 + Cu already balanced
d) AgNO3 + Na3PO4 --> Ag3PO4 + NaNO3
3AgNO3 + Na3PO4 --> Ag3PO4 + 3NaNO3
e) Ca + H2O --> H2 + Ca(OH)2 Ca + 2H2O --> H2 + Ca(OH)2
p. 258
# 7. a) 2K2O --> 4K + O2
decomposition
b) 2Na + I2 --> 2NaI
synthesis
c) Cu(NO3)2 + 2NaOH --> Cu(OH)2 + 2NaNO3
d) 2KClO3 --> 2KCl + 3O2
double displacement
decomposition
e) Ca(NO3)2 + 2HBr --> CaBr2 + 2HNO3 double displacement
f) Sn(OH)2 --> SnO + H2O
g) P4 + 6N2O --> P4O6 + 6N2
decompostion
single displacement
h) 3Fe + Al2(SO4)3 --> 3FeSO4 + 2Al
single displacement
i) 2AlCl3 + 3Na2CO3 --> Al2(CO3)3 + 6NaCl
double displacement
j) 2C3H6 + 9O2 --> 6CO2 + 6H2O
combustion
Nov 19­1:18 PM
1
Tuesday Oct 9 homework answers.notebook
October 09, 2012
Reaction or Not?
When two substances are mixed we can usually predict the
possible products by looking at the reactants.
Ex: sodium fluoride + potassium iodide -->
However, mixing two substances does not always result in a
reaction. A chemical reaction only occurs if the elements have a
stronger attraction of one of the other substances involved.
Mar 5­12:10 PM
What are the signs that a chemical reaction occurred?
pre
cip
ge
n
a
h
c
r
colou
ita
d
te
heat/lig
gas
uce
d
o
r
p
ht prod
uced
for
me
d
rse
e
v
e
r
d to
har
Mar 5­11:59 AM
2
Tuesday Oct 9 homework answers.notebook
October 09, 2012
Oct 9­9:37 AM
3