Question 1: Briefly explain the main idea behind the Particle Model of Matter.

Answer: The Particle Model of Matter states that all matter is made up of tiny particles that are in constant motion, and their arrangement and movement determine the state of the substance.

Question 1: Describe the arrangement and movement of particles in a solid.

Answer: Particles in a solid are closely packed in a fixed, regular pattern and vibrate in place with limited movement.

Question 2: Explain how particle movement differs in a gas compared to a liquid.

Answer: Particles in a gas are far apart, move rapidly in all directions, and are not fixed, unlike in liquids where particles are close but can slide past each other.

Question 1: What happens to particles during melting?

Answer: Particles gain energy, move faster, and break free from their fixed positions, changing from a solid to a liquid.

Question 2: Describe the particle behavior during condensation.

Answer: Particles lose energy, slow down, and come closer together, changing from a gas to a liquid.

Question 1: Calculate the energy required to convert 50 grams of ice at 0°C to water at 0°C. The specific heat of fusion for ice is 334 J/g.

Answer: 16700 J

Question 1: Design a simple experiment to demonstrate that heating increases particle movement in a liquid. Describe the variables involved and safety precautions.

Answer: Students can heat a small amount of water in a test tube held in a water bath, observing increased bubbling. Variables include temperature (independent), amount of water (controlled), and observation of boiling points. Safety precautions include wearing goggles, handling hot equipment carefully, and avoiding burns.

Question 1: A sample of gas is compressed into a smaller container at constant temperature. Explain what happens to the particles and why.

Answer: Particles are forced closer together, increasing their number of collisions, which results in higher pressure. This occurs because the particles have less space to move.

Question 1: Explain how the Particle Model helps in understanding the operation of a hot air balloon.

Answer: In a hot air balloon, heating the air increases particle energy, causing particles to move faster and spread out, decreasing the density and making the balloon rise.

Question 1: Why is the Particle Model important in explaining the properties of different states of matter?

Answer: The Particle Model explains how particle arrangement and movement determine the properties of solids, liquids, and gases, such as shape, volume, and compressibility.