Which one is not a process of purification of metals:

Options

A. chromatrography
B. zone refining
C. froth floatation
D. distillation

Answer

To determine which one is not a process of purification of metals among the options given (Chromatography, Zone refining, Froth flotation, and Distillation), we can analyze each process step by step.

### Step-by-Step Solution:

1. **Chromatography**:
- Chromatography is a method used for separating components of a mixture based on their different affinities towards a stationary phase and a mobile phase.
- In the context of metal purification, it can be used to separate and purify metals based on their density and solubility.
- **Conclusion**: Chromatography is a process of purification of metals.

2. **Zone Refining**:
- Zone refining is a technique used to purify crystalline solids, particularly metals.
- In this method, a molten zone is moved along a solid bar of metal, allowing impurities to concentrate in the molten zone while the pure metal crystallizes behind it.
- **Conclusion**: Zone refining is a process of purification of metals.

3. **Froth Flotation**:
- Froth flotation is a process used primarily for the concentration of sulfide ores.
- In this method, the ore is mixed with water and chemicals to create a froth. The desired minerals attach to the bubbles and float, while impurities sink.
- However, this process does not purify the metal itself; it only separates the ore from the gangue material.
- **Conclusion**: Froth flotation is not a process of purification of metals; it is a concentration process.

4. **Distillation**:
- Distillation is a separation technique that involves heating a liquid to create vapor and then cooling the vapor to create a liquid.
- In the context of metal purification, it can be used to separate metals from impurities based on their different boiling points.
- **Conclusion**: Distillation is a process of purification of metals.

### Final Answer:
The process that is **not** a method of purification of metals is **Froth Flotation**.

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