The common acid used in the manufacture of rayon and plastics is

Options

A. Methanoic acid
B. Ethanoic acid
C. Propanoic acid
D. Butanoic acid

Explanation

To solve the question regarding the common acid used in the manufacture of rayon and plastics, we can follow these steps:

### Step 1: Understand the question
The question asks for the common acid used in the manufacture of rayon and plastics. We need to identify the correct acid from the given options.

### Step 2: Review the options
The options provided are:
- Methanoic Acid
- Ethanoic Acid
- Propanoic Acid
- Butanoic Acid

### Step 3: Identify the acids
Let's briefly identify each acid:
- **Methanoic Acid (HCOOH)**: Also known as formic acid, it is the simplest carboxylic acid.
- **Ethanoic Acid (CH3COOH)**: Commonly known as acetic acid, it is a widely used organic compound.
- **Propanoic Acid (C2H5COOH)**: Also known as propionic acid, it is used as a preservative.
- **Butanoic Acid (C3H7COOH)**: Known as butyric acid, it has a strong odor and is found in rancid butter.

### Step 4: Research the uses of the acids
Among these acids, Ethanoic Acid (acetic acid) is known for its applications in various industries, including the production of rayon and plastics.

### Step 5: Conclusion
Based on the information gathered, the common acid used in the manufacture of rayon and plastics is **Ethanoic Acid (CH3COOH)**.

### Final Answer
The common acid used in the manufacture of rayon and plastics is **Ethanoic Acid**.

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