A Look Back at Chemistry 11
KEY
1. Convert the following into Scientific
Notation: (do not change sig figs)
727
7.27x102
172000
1.72x105
0.000984
9.84 x 10-4
200.0 x 102
2.000 x 104
0.014 x 102
1.4 x 100
2. Convert each into decimal form:
1.56x 104
15,600
3.6 x 10-2
0.036
736.9 x 105
73,690,000
0.0059 x 105
590
0.00059 x 10-1
0.000059
3. Calculate the following.
a) 2.34 x 1065
+ 9.2 x 1066
= 9.4 x 1066
b) 313.0
¬ 1.2 x 103
= -9 x 102
c) 8.95 x 1076 = 7.16 x 1071
1.25 X 105
d) (4.5 x 1029) (2.45 x 10100)
=1.1 x 10130
e) 17.34
4.900
+ 23.1
= 45.3
f) 9.80
¬ 4.762
= 5.04
g) 3.9 x 6.05 x 420 = 9.9 x 103
h) 14.1 = 3
4. Give The number of significant figures in each of the following:
a) 1.05 g
3
b) 0.0003040 mm
c) 29000 ft
2
d) 0.90 L
2
4
e) the number of eggs in a dozen INFINITE
HCl C3H8
SO2 NH4Cl KOH H2SO4
Al(OH)3 P2O5 Ba(OH)2 CH3COOH
H2O
AgNO3
PbSO4
H3PO4 Ca(OH)2
1. Classify the above as ionic or covalent by making two lists. Describe the difference between an ionic
and covalent compound.
Ionic
NH4Cl
KOH
Covalent
C3H8
SO2
AgNO3 PbSO4
H2O
Ca(OH)2
P2O5 H3PO4
Al(OH)3
Ba(OH)2
CH3COOH
Ionic compounds – formed when metal atoms transfer electrons to non-metal atoms.
Covalent compounds- formed when non-metal atoms share electrons
H2SO4
2. Classify the above as acids, bases, salts and molecular (covalent compounds) by making four lists.
Acids
HCl
H2SO4
CH3COOH
Bases
KOH
Ca(OH)2
Ba(OH)2
Salts
NH4Cl
AgNO3
PbSO4
Molecular
C3H8
SO2
H2 O
7. Write formulas or names of the following.
1. SnO2 tin (IV) oxide
2. silver phosphate Ag3PO4
3. mercury (II) carbonate
HgCO3
4. HCl hydrochloric acid
5. FeF3 iron (III) flouride
6. chromium (IV) sulfate
Cr(SO4)2
7. (NH4)2C2O4 ammonium
oxalate
8. silver thiosulfate
Ag2S2O3
14. hydrogen peroxide
H2O2
15. HgCr2O7
mercury (II) dichromate
16. barium acetate
Ba(CH3COO)2
17. MnSO3
manganese (II) sulfite
18. H2SO4
sulfuric acid
19. tungsten (II) phosphide
W3P2
20. ammonium hypochlorite
NH4ClO
9. aluminum hydrogen
phosphate Al2(HPO4)3
21. LiCN lithium cyanide
10. KClO4 potassium
perchlorate
22. NaH2PO4
sodium hydrogen biphosphate
11. Sn(ClO3)2
tin (II) chlorate
12. HNO3 nitric acid
13. zinc hydroxide Zn(OH)2
H3PO4
Al(OH)3
P2O5
7. Write a balanced chemical equation for the following reactions:
 sodium hydroxide
 iron + oxygen
sodium oxide + water
iron (III) oxide
 carbon dioxide + water
glucose + oxygen
 iron (II) sulfide + hydrochloric acid
iron (II) chloride + hydrogen sulfide
8. Given 100 grams of NH3:
a) how many molecules of ammonia are in the sample?
b) how many moles of ammonia are in the sample?
c) how many hydrogen atoms are in the sample?
d) what volume would the sample occupy at STP?
3. Describe how you can identify each of the four categories by the formula of the
compound.
Acids
The formula starts with H or ends in COOH except H2O.
Bases
The formula starts with a metal or NH4 and ends in OH.
Salts
The formula starts with a metal or NH4 and does not end in OH.
Molecular
The formula starts with a nonmetal other than H.
4. Calculate the molar mass of FeSO4 • 5H2O and Co3(PO4)2 • 6H2O.
241.9 g/mol
474.7 g/mol
5. 0.300 moles of NaCl is dissolved in 250.0 ml of water, calculate the molarity.
Molarity = 0.300 moles
=
1.20 M
.250 L
6. 500. g of FeSO4.6H2O is dissolved in 600. ml of water, calculate the molarity.
Molarity = 500g x 1 mole
259.9g
=
3.21 M
.600 L
7. How many grams of NaCl are required to prepare 100.0 ml of a 0.200 M solution?
.100L x 0.200 mole x 58.5 g
1L
1 mole
=
1.17g
8. 20. g of MgCl2 are dissolved in 250. ml of water, calculate the concentration of each ion.
20g x 1 mole
95.3 g
2+
Mg
+
Molarity =
-------->
= 0.84 M
2Cl-
MgCl2 -----
0.250 L
1.7 M
0.84 M
0.84 M
9. How many liters of 0.300 M NaCl contains 10.0 g of NaCl?
10.0g x
1 mole
58.5g
x
1L
0.300 mole
= 0.570 L
10. For each double replacement reaction write the formula equation, the complete ionic
equation and the net ionic equation.
a)
b)
H2SO4(aq)
+
------->
Na2SO4(aq)
2HOH(l)
SO42-(aq) + 2Na+(aq) + 2OH-(aq) ---------> 2Na+(aq) +
SO42-(aq)
+ 2HOH(l)
H+(aq) +
OH-(aq)
2H3PO4(aq)
6H+(aq)
+
--------->
HOH(l)
3Sr(OH)2(aq)
-------> Sr3(PO4)2(s)
2PO43-(aq) + 3Sr2+(aq) +
6OH-(aq)
2PO43-(aq) + 3Sr2+(aq) +
+
3Ca(NO3)2(aq)
+
2Na3PO4(aq)
--------->
6OH-(aq)
------->
3Ca2+(aq) + 6NO3-(aq) + 6Na+(aq) +
Zn(s)
+
--------->
+
6HOH(l)
Sr3(PO4)2(s)
+ 6HOH(l)
Sr3(PO4)2(s)
+ 6HOH(l)
Ca3(PO4)2(s) +
6NaNO3(aq)
2PO43-(aq) ----------> Ca3(PO4)2(aq) +
6Na+(aq) + 6NO3-(aq)
3Ca2+(aq) + 2PO43-(aq) ----------> Ca3(PO4)2(aq)
d)
+
2H+(aq) +
6H+(aq) +
c)
2NaOH (aq)
2HCl(aq) ---------> H2(g) +
ZnCl2(aq)
Zn(s)
+
2H+(aq) + 2Cl-(aq) ---------> H2(g) +
Zn(s)
+
2H+(aq) ---------> H2(g) +
Zn2+(aq) +
2Cl-(aq)
Zn2+(aq)
11. 25.0 g of sodium reacts with water, how many grams of hydrogen are produced? How
many grams of sodium hydroxide are produced?
2Na(s)
25.0 g Na x
25.0 g Na x
+ 2HOH(l) ---------> H2(g) + 2NaOH(aq)
1 mole
23.0 g
1 mole
23.0 g
x
x 1mol H2 x
2mol Na
2mol NaOH
2 mol Na
x
2.02 g
1 mole
40.0 g
1 mole
= 1.10 g
= 43.5 g
12. How many millilitres of 0.200M NaOH is required to neutralize 25.0 ml of 0.100 M
H2SO4 ?
+
H2SO4
2HOH
+
0.025 L
0.100 M
2NaOH ------------>
Na2SO4
?L
0.200 M
0.0250 L NaOH x 0.100 mole x 2 mole NaOH
x 1 L x 1000mL
1L
1 mole H2SO4 0.200mole
1L
= 25.0 mL
13. A beaker of mass = 25.36g contains 2.00 L of a solution of BaCl2 and is evaporated to
dryness mass = 28.59 g. Calculate the molarity of the solution.
28.59g – 25.36 =3.23g
Molarity = 3.23g x 1 mole
208.3g
=
0.00775 M
2.00 L
CHALLENGE!!!
14.
A 0.960 g sample of impure Na2CO3 is dissolved in water and then completely
reacted with 0.200 M HCl requiring 65.3 mL. Calculate the percentage by mass of
Na2CO3 in the sample.
Na2CO3
+
2HCl 
CO2
+
2NaCl
+
H2O
0.00653 L
?g
0.200 M
0.0653 L HCl
=
x
0.200 moles x
1L
1 mole Na2CO3
2 mol HCl
x 106 g
=
0.069218 g x
0.960 g
100
7.21 %
0.069218g
%
%
=