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Copper can be produced by reacting copper sulfide with oxygen.

The balanced equation for the reaction is:
[tex]\[
2Cu_2S + 3O_2 \longrightarrow 4Cu + 2SO_2
\][/tex]

The atom economy for the production of copper in this reaction is 66.5%. Explain why you might choose to extract copper from copper oxide (Cu_2O) rather than copper sulfide (Cu_2S).

[1 mark]

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The sulfur dioxide (SO_2) can also be used to make sulfuric acid. Suggest how this will affect the atom economy of the reaction.

[1 mark]

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Answer :

### Why You Might Choose to Extract Copper from Copper Oxide [tex]\( Cu_2O \)[/tex] Rather than Copper Sulfide [tex]\( Cu_2S \)[/tex]

When choosing between extracting copper from copper oxide [tex]\( Cu_2O \)[/tex] or copper sulfide [tex]\( Cu_2S \)[/tex], there are several considerations that might lead you to prefer [tex]\( Cu_2O \)[/tex]:

1. Less Harmful Byproducts: The extraction of copper from [tex]\( Cu_2S \)[/tex] produces sulfur dioxide [tex]\( SO_2 \)[/tex], a harmful gas that can contribute to air pollution and acid rain. In contrast, extracting copper from [tex]\( Cu_2O \)[/tex] produces fewer harmful byproducts.

2. Availability and Abundance: Copper oxide [tex]\( Cu_2O \)[/tex] might be more readily available or more abundant in nature compared to copper sulfide [tex]\( Cu_2S \)[/tex]. This can make the extraction process more feasible and cost-effective.

### How Using Sulfur Dioxide [tex]\( SO_2 \)[/tex] to Make Sulfuric Acid Will Affect the Atom Economy

Using the byproduct sulfur dioxide [tex]\( SO_2 \)[/tex] to produce sulfuric acid can improve the atom economy of the reaction. Atom economy is a measure of the efficiency of a reaction in terms of the mass of the desired product(s) relative to the total mass of the reactants. If the byproduct [tex]\( SO_2 \)[/tex] can be utilized to make sulfuric acid, it means that:

- The byproduct [tex]\( SO_2 \)[/tex] is not wasted, leading to better resource utilization.
- The overall efficiency of the reaction increases because a secondary valuable product (sulfuric acid) is obtained from the initial byproduct.

This utilization enhances the sustainability and economic viability of the process, thereby contributing positively to the atom economy.