Question

question 8

consider the following chemical reaction:

\\(\text{fe}_2\text{o}_3 + 3\text{cl}_2 \
ightarrow 2\text{fe} + 3\text{cl}_2\text{o}\\)

what is oxidized and what is reduced in this reaction?

oxygen is reduced and iron is oxidized.
iron is reduced and chlorine is oxidized.
none. this is not a redox reaction!
chlorine is reduced and oxygen is oxidized.
chlorine is reduced and iron is oxidized.

Explanation:

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<reasoning>

Assign oxidation states to reactants

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{In } \text{Fe}_2\text{O}_3: \text{O} = -2, \quad \text{Fe} = +3\\ &\text{In } \text{Cl}_2: \text{Cl} = 0 \end{aligned}$$

\]

Assign oxidation states to products

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{In } \text{Fe}: \text{Fe} = 0\\ &\text{In } \text{Cl}_2\text{O}: \text{O} = -2, \quad \text{Cl} = +1 \end{aligned}$$

\]

Identify oxidized and reduced species

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{Fe: } +3 ightarrow 0 \quad (\text{decrease in oxidation state} \implies \text{reduced})\\ &\text{Cl: } 0 ightarrow +1 \quad (\text{increase in oxidation state} \implies \text{oxidized})\\ &\text{O: } -2 ightarrow -2 \quad (\text{no change}) \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>Oxygen is reduced and iron is oxidized.</mcq-option>
<mcq-correct>Iron is reduced and chlorine is oxidized.</mcq-correct>
<mcq-option>None. This is not a redox reaction!</mcq-option>
<mcq-option>Chlorine is reduced and oxygen is oxidized.</mcq-option>
<mcq-option>Chlorine is reduced and iron is oxidized.</mcq-option>
</answer>

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Answer:

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<reasoning>

Assign oxidation states to reactants

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{In } \text{Fe}_2\text{O}_3: \text{O} = -2, \quad \text{Fe} = +3\\ &\text{In } \text{Cl}_2: \text{Cl} = 0 \end{aligned}$$

\]

Assign oxidation states to products

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{In } \text{Fe}: \text{Fe} = 0\\ &\text{In } \text{Cl}_2\text{O}: \text{O} = -2, \quad \text{Cl} = +1 \end{aligned}$$

\]

Identify oxidized and reduced species

Using the Oxidation State Rules and Oxidation Number Calculation knowledge points
\[

$$\begin{aligned} &\text{Fe: } +3 ightarrow 0 \quad (\text{decrease in oxidation state} \implies \text{reduced})\\ &\text{Cl: } 0 ightarrow +1 \quad (\text{increase in oxidation state} \implies \text{oxidized})\\ &\text{O: } -2 ightarrow -2 \quad (\text{no change}) \end{aligned}$$

\]
</reasoning>

<answer>
<mcq-option>Oxygen is reduced and iron is oxidized.</mcq-option>
<mcq-correct>Iron is reduced and chlorine is oxidized.</mcq-correct>
<mcq-option>None. This is not a redox reaction!</mcq-option>
<mcq-option>Chlorine is reduced and oxygen is oxidized.</mcq-option>
<mcq-option>Chlorine is reduced and iron is oxidized.</mcq-option>
</answer>

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