Change of State Big Q - What happens to the particles of a solid as it melts? Big Q - What happens to the particles of a liquid as it vaporizes? Big Q - What happens to the particles of a solid as it sublimes?

Engage - On the boil You might have noticed that as an uncovered pot of water boils, the water level slowly decreases. The water level changes because the liquid is changing to a gas. As you heat the water, the thermal energy of its molecules increases. The longer you leave the pot on the hot stove, the more energy is absorbed by the water molecules. When the water molecules gain enough energy, they change state from a liquid to a gas. The graph shows the temperature of a small pot of water on a stove set to high heat. The starting temperature of the water is 20°C

Engage - On the boil How long does it take for the water to start boiling? At what temperature does the water boil? Does it take more energy to heat the water to 100℃ or to boil it?

Explore - What happens when you breathe on a mirror? Investigate why the mirror fogs when you breathe on it. ****Answer questions on your Inquiry Warm-Up Worksheet

Explain - Unit Vocabulary Melting Freezing Melting/Freezing Point solid to liquid Liquid to solid temperature stops increasing or decreasing at 0℃

Explain - phase diagram What does the solid need to gain in order to become a liquid? -Melting gains heat energy -Freezing loses heat energy

Explain - unit vocabulary Vaporization Evaporation Boiling Condensation Boiling/Condensation Point liquid to gas occurs on the surface of a liquid occurs below the surface of a liquid gas to liquid temperature stops increasing or decreasing at 100℃

Explain - Phase diagram Describe the heat energy as a liquid moves to a gas? Vaporization gains heat energy!

Explain - Unit Vocabulary Sublimation - occurs when a solid moves directly to gas without going through the liquid state.

Elaborate - Phase Changes Investigate how the states of matter change when heat is added. ***Answer questions in your lab packet

Evaluate - Change of state Please complete your exit ticket