In order to refine “blister copper” it is melted in a furnace and is stirred with green logs of wood. The purpose is

Options

A. To expel the dissolved gases in blister copper
B. To bring the impurities to surface and oxidize them
C. To increase the carbon content of copper
D. To reduce the metallic oxide impurities with hydrocarbon gases liberated from the wood

Explanation

To refine blister copper, the process involves melting the copper in a furnace and stirring it with green logs of wood. Here’s a step-by-step explanation of the purpose of this process:

### Step 1: Melting the Blister Copper
- **Explanation**: Blister copper, which contains impurities including oxides, is first melted in a furnace. This is necessary to allow for the separation of these impurities from the pure copper.

### Step 2: Stirring with Green Logs of Wood
- **Explanation**: The molten copper is then stirred with green logs of wood. The wood is chosen specifically for its moisture content and organic compounds.

### Step 3: Reaction with Hydrocarbons
- **Explanation**: When the green wood is introduced to the molten copper, it releases hydrocarbon gases. These gases react with the metallic oxide impurities present in the blister copper.

### Step 4: Reduction of Metallic Oxides
- **Explanation**: The hydrocarbons act as reducing agents. They reduce the metallic oxides (such as CuO) to metallic copper, effectively removing the impurities. This reduction reaction is crucial for purifying the copper.

### Step 5: Resulting Purification
- **Explanation**: As a result of this process, the impurities are removed, and the copper is refined to a higher purity level, making it suitable for further use in various applications.

### Summary
The purpose of stirring blister copper with green logs of wood during its melting process is to reduce the metallic oxide impurities through the action of hydrocarbon gases released from the wood.

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