What is usually added to ethyl alcohol to make it unfit for drinking purposes?

Explanation

To answer the question, "What is usually added to ethyl alcohol to make it unfit for drinking purposes?" we can follow these steps:

### Step 1: Understand Ethyl Alcohol
Ethyl alcohol, also known as ethanol, is a common type of alcohol that is consumable in beverages. Its chemical formula is C2H5OH or CH3CH2OH.

### Step 2: Identify the Need for Denaturing
In industrial applications, ethyl alcohol is often denatured to prevent it from being consumed. This is done to avoid taxation and regulation associated with alcoholic beverages.

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