Solids, liquids and gases：練習問題

When a substance changes state from a solid to a liquid, what happens to the arrangement and movement of its particles?

Bromine vapor (\( Br_2 \)) is heavier than air. If a jar of air is inverted over a jar of bromine vapor, the brown color eventually spreads throughout both jars. Which statement best explains this observation in terms of the kinetic theory of matter?

Potassium manganate(VII) crystals (\( KMnO_4 \)) are placed at the bottom of a beaker of water. After several hours, the entire solution turns purple. If this experiment were repeated using water at \( 5^\circ C \) instead of \( 25^\circ C \), which of the following would be observed?

A substance is heated at a constant rate. Which of the following statements correctly describes the energy changes occurring during melting?

When a solid undergoes sublimation directly into a gas, which of the following best describes the change in the distance between particles and the energy change involved?

Describe the difference in the movement of particles in a solid compared to those in a liquid.

Using the kinetic theory of matter, explain why the rate of diffusion of ammonia gas decreases as the temperature is lowered.

A gas syringe contains a sample of bromine gas, \( Br_2 \). Explain why the volume of the gas decreases significantly when the plunger is pushed, whereas the volume of a syringe filled with water does not change under the same pressure.

A substance is observed changing from a state where its particles are in a regular, fixed lattice arrangement to a state where the particles remain close together but are able to move and slide past each other.

a. Name the inter-conversion process described above.
b. State whether thermal energy is absorbed from the surroundings or released to the surroundings during this change of state.
c. Describe how the movement of the particles changes as this process occurs.

Compare the properties of solids and gases in terms of their compressibility and shape.

a. Use the kinetic theory to explain why gases are easily compressed but solids are not.
b. Use the particle model to explain why solids have a fixed shape while gases expand to fill their container.