Question 1
Without doing any calculations, determine whether the standard entropy change, Δ
S° is positive or negative for each of the following reactions.
reaction 1: S(
s, rhombic) + O
2(
g) → SO
2(
g)
reaction 2: 2 SO
2(
g)+ O
2(
g) → 2 SO
3(
g)
◦ Δ
S° is positive for both reactions.
◦ Δ
S° is negative for both reactions.
◦ Δ
S° is positive for reaction 2 but negative for reaction 1.
◦ Δ
S° is positive for reaction 1 but negative for reaction 2.
Question 2
Sodium reacts violently with water according to the equation:
2 Na(s) + 2 H2O(l) → 2 NaOH(aq) + H2(g)
The resulting solution has a higher temperature than the water prior to the addition of sodium. What are the signs of Δ
H° and Δ
S° for this reaction?
◦ Δ
H° is negative and Δ
S° is negative.
◦ Δ
H° is positive and Δ
S° is positive.
◦ Δ
H° is negative and Δ
S° is positive.
◦ Δ
H° is positive and Δ
S° is negative.
Sodium Balance
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