Ethanol is commercially obtained by

Options

A. destructive distillation
B. fermentation
C. vacuum distillation
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Ethanol Production**: Ethanol is a type of alcohol that is commonly used in beverages and industrial applications. To determine how it is commercially obtained, we need to look at the common methods of production.

2. **Fermentation Process**: The primary method for producing ethanol on a commercial scale is through fermentation. This process involves the conversion of sugars into ethanol and carbon dioxide by microorganisms, typically yeast.

3. **Role of Yeast**: Yeast, a type of fungus, plays a crucial role in fermentation. It metabolizes sugars (like glucose) in the absence of oxygen, which is known as anaerobic respiration.

4. **Chemical Reaction**: The overall chemical reaction for fermentation can be represented as follows:
\[ C_6H_{12}O_6 \, (\text{sugar}) \xrightarrow{\text{yeast}} 2 \, C_2H_5OH \, (\text{ethanol}) + 2 \, CO_2 \, (\text{carbon dioxide}) \]
Here, glucose (C6H12O6) is converted into ethanol (C2H5OH) and carbon dioxide (CO2).

5. **Conclusion**: Therefore, the commercial production of ethanol is primarily achieved through the fermentation of sugars by yeast.

**Final Answer**: Ethanol is commercially obtained by the process of fermentation.

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