An ore of tin containing `FeCrO_(4)` is concentrated by _____.

Options

A. gravity separation
B. magnetic separation
C. froth floatation
D. leaching

Explanation

To solve the question regarding the concentration of an ore of tin containing FeCrO₄, we will analyze the options provided and determine the most appropriate method for concentration.

### Step-by-Step Solution:

1. **Understanding the Ore Composition**:
- The ore in question contains FeCrO₄, which is known as chromite. It is important to note that FeCrO₄ has ferromagnetic properties.

2. **Analyzing the Concentration Methods**:
- **Gravity Separation**: This method is based on the difference in density between the ore and the gangue. It is typically used for denser ores but is not specifically effective for separating materials based on magnetic properties.

- **Magnetic Separation**: This method exploits the differences in magnetic properties of the components in the ore. Since FeCrO₄ is ferromagnetic and tin is non-magnetic, this method can effectively separate the two based on their magnetic characteristics.

- **Froth Flotation**: This process is used to separate hydrophobic materials from hydrophilic ones. It is not suitable for the concentration of FeCrO₄ in this context.

- **Leaching**: This chemical process involves dissolving the ore in a solution to separate the metal from impurities. While effective for some ores, it is not the primary method for concentrating ores with magnetic properties.

3. **Conclusion**:
- Given that FeCrO₄ is ferromagnetic and tin is non-magnetic, the most suitable method for concentrating the ore of tin containing FeCrO₄ is **magnetic separation**.

### Final Answer:
The ore of tin containing FeCrO₄ is concentrated by **magnetic separation**.

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