The correct option is **B. Gas particles are free to move independently and are far apart, with negligible intermolecular forces.** ### Detailed Explanation: 1. **Understanding the States of Matter**: - Matter exists in different states: solid, liquid, and gas. Each state has distinct characteristics based on the arrangement and behavior of its particles. 2. **Behavior of Gas Particles**: - In a gas, particles are **far apart** compared to those in solids and liquids. This large distance between particles allows them to move freely and independently of one another. - The **intermolecular forces** in gases are very weak, which means that gas particles do not stick together. This lack of strong attraction allows them to fill the entire volume of their container, leading to the property of gases having no definite shape or volume. 3. **Kinetic Molecular Theory**: - The behavior of gas particles can be explained by the **Kinetic Molecular Theory**, which states that: - Gas particles are in constant, random motion. - The speed of the particles increases with temperature. - Collisions between gas particles and the walls of their container are elastic, meaning that no energy is lost in these collisions. 4. **Why Option B is Correct**: - Option B accurately describes the nature of gas particles: they are independent, far apart, and experience negligible intermolecular forces. This is a fundamental characteristic of gases that distinguishes them from liquids and solids. ### Why the Other Options are Incorrect: - **Option A: Gas particles are closely packed together and vibrate in place.** - This statement is incorrect because it describes the behavior of particles in a solid, not a gas. In solids, particles are indeed closely packed and can only vibrate in fixed positions. Gases, on the other hand, have particles that are not closely packed and can move freely. - **Option C: Gas particles have a definite shape and volume.** - This statement is also incorrect. Gases do not have a definite shape or volume; they take the shape and volume of their container. This is a key difference between gases and liquids, which have a definite volume but take the shape of their container. - **Option D: Gas particles are tightly bound in fixed positions and can only rotate.** - This statement is incorrect as it describes the behavior of particles in a solid. In gases, particles are not tightly bound; they are free to move in all directions. The ability to rotate is not a defining characteristic of gas particles, as they are not fixed in position. ### Summary of Key Points: - Gas particles are far apart and move independently, with negligible intermolecular forces. - Gases have no definite shape or volume, filling the container they are in. - The Kinetic Molecular Theory explains the behavior of gas particles, emphasizing their constant motion and elastic collisions. - Understanding the differences between the states of matter is crucial for grasping the properties of gases compared to liquids and solids.