Which statement best describes a gas?

Which statement best describes a gas?

• A. Particles are tightly packed and vibrate in place
• B. Particles move freely past each other but aren't free to move far apart
• C. Particles are far apart with no definite shape or volume
• D. Particles are charged at very high temperatures

Answer: (B)

Gas is defined by particles that are far apart and move freely, filling the space of their container so they have no definite shape or volume. The particles are in rapid, random motion with lots of empty space between them, and they collide as they spread to fill the available area. This is why gases expand to fill their container and can be compressed. The statement that best describes a gas captures this idea of wide spacing and free movement. In contrast, a solid has tightly packed particles that mainly vibrate in place, and a liquid has particles that can slide past each other but remain fairly close together. The idea of particles being charged at very high temperatures points to plasma, which is a different state where atoms ionize, not the general behavior of a gas.

Gas is defined by particles that are far apart and move freely, filling the space of their container so they have no definite shape or volume. The particles are in rapid, random motion with lots of empty space between them, and they collide as they spread to fill the available area. This is why gases expand to fill their container and can be compressed.

The statement that best describes a gas captures this idea of wide spacing and free movement. In contrast, a solid has tightly packed particles that mainly vibrate in place, and a liquid has particles that can slide past each other but remain fairly close together. The idea of particles being charged at very high temperatures points to plasma, which is a different state where atoms ionize, not the general behavior of a gas.