Particle Model of Matter questions and answers

📚 Quick Study Guide

• 🔬 The particle model describes matter as being made up of tiny particles (atoms, molecules, or ions) that are constantly moving.
• 🌡️ Temperature is a measure of the average kinetic energy of the particles. Higher temperature means faster-moving particles.
• 🧊 Solids have a fixed shape and volume because the particles are tightly packed and vibrate in fixed positions.
• 💧 Liquids have a fixed volume but can change shape because the particles are close together but can move past each other.
• 💨 Gases have no fixed shape or volume because the particles are far apart and move randomly.
• ✨ Changes of state (melting, boiling, freezing, condensation, sublimation, deposition) involve changes in the arrangement and energy of the particles.
• 🔥 Heating a substance increases the kinetic energy of its particles.
• 📏 Diffusion is the process by which particles spread out from an area of high concentration to an area of low concentration. The rate of diffusion increases with temperature and decreases with particle size.
• 🧮 Brownian motion is the random movement of particles in a fluid, caused by collisions with other particles.

🧪 Practice Quiz

1. What is the main assumption of the particle model of matter?
   1. Particles are stationary.
   2. Particles are constantly moving.
   3. Particles do not interact with each other.
   4. Particles are only present in solids.
2. Which state of matter has particles that are tightly packed and vibrate in fixed positions?
   1. Liquid
   2. Gas
   3. Solid
   4. Plasma
3. What happens to the average kinetic energy of particles when the temperature of a substance increases?
   1. It decreases.
   2. It stays the same.
   3. It increases.
   4. It becomes zero.
4. Which process involves a substance changing from a liquid to a gas?
   1. Freezing
   2. Melting
   3. Condensation
   4. Boiling
5. What is diffusion?
   1. The process by which particles stop moving.
   2. The process by which particles spread out from an area of low concentration to an area of high concentration.
   3. The process by which particles spread out from an area of high concentration to an area of low concentration.
   4. The process by which particles clump together.
6. Which of the following factors affects the rate of diffusion?
   1. Volume
   2. Mass
   3. Temperature
   4. Density
7. What is Brownian motion?
   1. The movement of large objects in a fluid.
   2. The random movement of particles in a fluid.
   3. The orderly movement of particles in a solid.
   4. The absence of movement in particles.