The correct option for the synthetic polymer commonly used in the production of plastic bottles and containers due to its durability and resistance to chemicals is **B. Polyethylene terephthalate (PET)**. ### Detailed Explanation 1. **Understanding the Options**: - **A. Polystyrene**: This polymer is often used in packaging materials, disposable cutlery, and insulation. While it is lightweight and can be molded easily, it is not particularly resistant to chemicals and is not typically used for bottles that require durability. - **B. Polyethylene terephthalate (PET)**: PET is a strong, lightweight plastic that is highly resistant to impact and chemicals. It is commonly used for making beverage bottles, food containers, and other packaging materials. Its properties make it ideal for applications where durability and chemical resistance are crucial. - **C. Polyvinyl chloride (PVC)**: PVC is used in a variety of applications, including pipes, medical devices, and flooring. While it is durable, it is not typically used for food and beverage containers due to potential leaching of harmful chemicals. - **D. Polypropylene**: This polymer is known for its toughness and resistance to heat. It is used in a variety of applications, including automotive parts and food containers. However, it is less commonly used for beverage bottles compared to PET. 2. **Why PET is the Correct Answer**: - **Durability**: PET is known for its high tensile strength, which means it can withstand significant stress without breaking. This makes it ideal for bottles that need to hold carbonated beverages under pressure. - **Chemical Resistance**: PET is resistant to many chemicals, which is essential for storing various liquids without the risk of degradation or contamination. - **Recyclability**: PET is one of the most recycled plastics globally, making it an environmentally friendly choice for manufacturers and consumers. - **Clarity and Aesthetic Appeal**: PET is clear and can be made to have a glossy finish, which is visually appealing for consumer products. 3. **Why the Other Options are Incorrect or Weaker**: - **Polystyrene (A)**: While it is versatile, it is brittle and can break easily. It is not suitable for applications requiring high durability and chemical resistance, such as beverage containers. - **Polyvinyl Chloride (C)**: Although it is durable, PVC can release harmful chemicals, especially when heated or when in contact with certain substances. This makes it unsuitable for food and beverage applications. - **Polypropylene (D)**: While it has good chemical resistance and is used in some food containers, it is not as widely used for beverage bottles as PET. It also has a lower clarity compared to PET, which is often preferred for consumer products. ### Summary of Key Points - **Correct Answer**: B. Polyethylene terephthalate (PET) is the most suitable polymer for plastic bottles and containers due to its durability and chemical resistance. - **Properties of PET**: High tensile strength, chemical resistance, recyclability, and aesthetic appeal. - **Limitations of Other Options**: Polystyrene is brittle, PVC can leach harmful chemicals, and polypropylene is less common for beverage bottles compared to PET. - **Environmental Consideration**: PET is widely recycled, making it a more sustainable choice in the plastic industry. This thorough understanding of the properties and applications of these polymers will help you in your exam preparation and in recognizing the best materials for specific uses in chemistry and materials science.