Chemistry Reference
In-Depth Information
The sum of the first two equations is the third, and the same is
true for the heats of reaction:
10.13
(a)
A
2 B
£
C
2 D
Change:
(b)
1.00 mol
2.00 mol
1.00 mol
2.00 mol
59.4 kJ
2.5 kJ
61.9 kJ
A
2 B
£
C
3 D
The spectator ions do not contribute to the heat of reaction
because they do not react.
Change:
(c)
1.00 mol
2.00 mol
1.00 mol
3.00 mol
2 A
3 B
£
C
2 D
Change:
(d)
4.00 mol
6.00 mol
2.00 mol
4.00 mol
A
3 B
£
C
2 D
10 Stoichiometry
Change:
0.150 mol
0.450 mol
0.150 mol
0.300 mol
2 mol Al
3 mol Cl
2
2 mol Al
2 mol AlCl
3
3 mol Cl
2
2 mol AlCl
3
10.14
(a)
A
B
£
2 C
2 D
10.1
Initial:
1.00 mol
1.10 mol
0.00 mol
0.00 mol
3 mol Cl
2
2 mol Al
2 mol AlCl
3
2 mol Al
2 mol AlCl
3
3 mol Cl
2
Change:
Final:
1.00 mol
1.00 mol
2.00 mol
2.00 mol
0.00 mol
0.10 mol
2.00 mol
2.00 mol
(b)
A
2 B
£
C
2 D
10.3
(a)
36 HCl molecules
(b)
72 HCl molecules
(c)
300 HCl molecules
(d)
3 dozen HCl molecules
Initial:
3.00 mol
4.00 mol
0.00 mol
0.00 mol
(e)
3 mol HCl
(f)
9 mol HCl
Change:
2.00 mol
4.00 mol
2.00 mol
4.00 mol
Final:
1.00 mol
0.00 mol
2.00 mol
4.00 mol
10.5
All of them. (The equation merely gives the
mole ratio,
not
any particular number of moles.)
(c)
2 A
3 B
£
C
2 D
14 mol HCl
2 mol CrCl
3
7 mol HCl
1 mol CrCl
3
Initial:
1.50 mol
4.00 mol
0.000 mol
0.00 mol
10.7
Change:
Final:
1.50 mol
2.25 mol
0.750 mol
1.50 mol
0.00 mol
1.75 mol
0.750 mol
1.50 mol
10.8
(a)
CoCl
2
2 AgC
2
H
3
O
2
£ 2 AgCl
Co(C
2
H
3
O
2
)
2
(d)
A
2 B
£
C
2 D
a
1 mol CoCl
2
2 mol AgCl
2.20 mol AgCl
b
1.10 mol CoCl
2
Initial:
0.750 mol
1.25 mol
0.000 mol
0.10 mol
Change:
0.625 mol
1.25 mol
0.625 mol
1.25 mol
(b)
CrCl
2
2 AgC
2
H
3
O
2
£ 2 AgCl
Cr(C
2
H
3
O
2
)
2
Final:
0.125 mol
0.00 mol
0.625 mol
1.35 mol
a
1 mol CrCl
2
2 mol AgCl
10.16
Decomposition reactions have only one reactant.
2.20 mol AgCl
b
1.10 mol CrCl
2
10.17
(a)
2.00 mol
(b)
No (There is no assurance that all the
(c)
CaCl
2
2 AgC
2
H
3
O
2
£ 2 AgCl
Ca(C
2
H
3
O
2
)
2
H
2
reacts.)
(c)
Yes (4.50 mol)
a
1 mol CaCl
2
2 mol AgCl
2.20 mol AgCl
b
1.10 mol CaCl
2
10.18
(a)
3 mol
(b)
3 mol [The number of moles of HCl is the limiting quan-
tity, even though it is greater than the number of moles
of
(c)
2 mol [The
10.9
(a)
NH
4
Cl(aq)
AgC
2
H
3
O
2
(aq) £
AgCl(s)
NH
4
C
2
H
3
O
2
(aq)
La(OH)
3
.]
a
1 mol NH
4
Cl
1 mol AgCl
La(OH)
3
is present in limiting quantity.]
0.700 mol AgCl
b
0.700 mol NH
4
Cl
10.19
3 NaOH(aq)
H
3
PO
4
(aq) £ Na
3
PO
4
(aq)
3 H
2
O(
/
)
(b)
ZnCl
2
(aq)
2 AgC
2
H
3
O
2
(aq) £
a
1 mol H
3
PO
4
3 mol NaOH
2 AgCl(s)
Zn(C
2
H
3
O
2
)
2
(aq)
1.29 mol NaOH
b
0.430 mol H
3
PO
4
a
1 mol ZnCl
2
2 mol AgCl
0.700 mol AgCl
b
0.350 mol ZnCl
2
2 HCl(aq) £ ZnCl
2
(aq)
H
2
(g)
10.23
Zn(s)
6 HCl(aq) £ 2 AlCl
3
(aq)
3 H
2
(g)
2 Al(s)
(c)
AlCl
3
(aq)
3 AgC
2
H
3
O
2
(aq) £
3 AgCl(s)
Al(C
2
H
3
O
2
)
3
(aq)
2 HCl(aq) £ MgCl
2
(aq)
H
2
(g)
Mg(s)
a
1 mol AlCl
3
3 mol AgCl
The sample of aluminum can produce the most hydrogen
because there is a mole ratio of hydrogen to aluminum
metal in the balanced equation for that reaction and only a
mole ratio in the other two equations. That is, each mole
of aluminum produces more hydrogen.
0.700 mol AgCl
b
0.233 mol AlCl
3
3:2
10.10
(a)
12 sandwiches
(b)
12 sandwiches (This problem involves a limiting quan-
tity; you cannot make 14 sandwiches with only 24 slices
of bread.)
(c)
11 sandwiches (You cannot make 12 sandwiches with
only 11 patties.)
(d)
The quantities of two (or more) reactants are given in
the problem statement.
1:1
10.26
Note that
incomplete combustion
means formation of CO
rather than
CO
2
.
The balanced equation is
2 C
8
H
18
(
/
)
17 O
2
(g) £ 16 CO(g)
18 H
2
O(
/
)
17 mol O
2
2 mol C
8
H
18
7.80 mol C
8
H
18
a
b
66.3 mol O
2
10.11
(a)
No NaBr can be produced without any bromine.
(b)
2 mol of NaBr can be produced. The numbers of moles
present are exactly the same as the coefficients in the
balanced equation.
(c)
2 mol of NaBr can be produced. The sum of the numbers
of moles of reactants in parts (a) and (b) produces the
sum of the numbers of moles of products. Put another
way, after 1 mol of
a
1 mmol CrO
4
2
3 mmol Co
2
7.00 mmol Co
2
10.30
(a)
b
2.33 mmol CrO
4
2
a
4 mmol H
2
O
3 mmol Co
2
7.00 mmol Co
2
(b)
b
9.33 mmol H
2
O
Br
2
reacts with 2 mol of Na, as in part
Heat
(b), there is no more
Br
2
left, and we are back to the sit-
10.31
(a)
(b)
The product (Not all of the HgO reacted.)
2 HgO(s)
¡
2 Hg(
/
)
O
2
(g)
uation in part (a).
