11. Balance the following redox equation occurring in aqueous solution:
KMnO
4
+ KCl + H
2
SO
4
→
MnSO
4
+ K
2
SO
4
+ H
2
O + Cl
2
What is the stoichiometric coefficient for chlorine (Cl
2
) when the equation is balanced
with smallest whole number coefficients?
a. 1
b. 3
c. 5
d. 8
e. 10
Thermodynamics and Thermochemistry
1. Data:
(1) H
2
(
g
) + ½O
2
(
g
)
→
H
2
O(
g
)
Δ
H
= -241.8 kJ
(2) H
2
(
g
) + ½O
2
(
g
)
→
H
2
O(
l
)
Δ
H
= -285.8 kJ
On the basis of the above data, which of the following statements is
false
?
a.
Reaction (1) is exothermic.
b.
Reaction (2) is the formation reaction for H
2
O(
l
).
c.
The reverse of reaction (2) is endothermic.
d.
The energy content of H
2
O(
g
) is lower than H
2
O(
l
).
e.
Δ
H
for the reaction: H
2
O(
l
)
→
H
2
O(
g
) is + 44 kJ/mol.
2. What is the amount of heat necessary to raise the temperature of 8.5 kg of water from
12.5 °C to 84 °C?
a.
3.0 x 10
3
kJ
b.
36 J
c.
2.5 x 10
3
kJ
d.
2.5 x 10
6
kJ
e.
25 kJ
3. Data:
Δ
H
°
f
values: CH
4
(
g
), -74.8 kJ; CO
2
(
g
), -393.5 kJ; H
2
O(
l
), -285.8 kJ.
Using the
Δ
H
°
f
data above, calculate
Δ
H
°
rxn
for the reaction below.
Reaction: CH
4
(
g
) + 2O
2
(
g
)
→
CO
2
(
g
) + 2H
2
O(
l
)
a.
-604.2 kJ
b.
890.3 kJ
c.
-997.7 kJ
d.
-890.3 kJ
e.
none of the above