Which of these was the first fully-synthetic fibre to be manufactured?

Options

A. Acrylic
B. Nylon
C. Polyester
D. Rayon

Explanation

**Step-by-Step Solution:**

1. **Understanding Synthetic Fibers**: Synthetic fibers are man-made fibers created through chemical processes. They differ from natural fibers, which are derived from plants or animals.

2. **Identifying Types of Fibers**: The question asks for the first fully synthetic fiber. It’s important to differentiate between fully synthetic and partially synthetic fibers.

3. **Analyzing Rayon**: Rayon is mentioned as a fiber that is derived from plant cellulose. Since it originates from natural sources, it is classified as a partially synthetic fiber, not fully synthetic.

4. **Identifying Nylon**: The video mentions nylon as a fully synthetic fiber. It is created through the polymerization of specific chemicals, namely adipic acid and hexamethylene diamine.

5. **Chemical Composition of Nylon**: Nylon is produced by combining adipic acid (C6H10O4) and hexamethylene diamine (C6H16N2) through a condensation reaction, which results in the formation of nylon and the release of water.

6. **Conclusion**: Based on the information provided, the first fully synthetic fiber to be manufactured is nylon.

**Final Answer**: The first fully synthetic fiber to be manufactured is **Nylon**.

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