Froth floatation process is used for the concentration of the ore of :

Options

A. Fe
B. Al
C. Cr
D. Cu

Answer

To determine which ore is concentrated using the froth flotation process, let's analyze the options provided:

### Step 1: Understand the Froth Flotation Process
The froth flotation process is a method used for separating hydrophobic materials from hydrophilic ones. It is primarily used for the concentration of sulfide ores.

### Step 2: Analyze Each Option
1. **Iron**: Iron ores, such as hematite (Fe2O3), are primarily oxide ores. The froth flotation process is not typically used for these types of ores.

2. **Aluminium**: Aluminium is extracted from bauxite, which is primarily composed of aluminum oxide (Al2O3). This is also an oxide ore, and froth flotation is not used for its concentration.

3. **Chromium**: Chromium ores, such as chromite (FeCr2O4), are also not concentrated using the froth flotation process, as they are typically treated through other methods.

4. **Copper**: Copper is often found in sulfide ores, such as chalcopyrite (CuFeS2) and chalcocite (Cu2S). The froth flotation process is commonly used for the concentration of these sulfide ores.

### Step 3: Conclusion
Based on the analysis, the correct answer is that the froth flotation process is used for the concentration of the ore of **Copper**.

### Final Answer:
**Copper (Option 4)**

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