"Sublimation and Sublimation" State of Matter and Its Changes PPT Courseware 4

Description

"Sublimation and Sublimation" State of Matter and Its Changes PPT Courseware 4

Try this: Can you give an example in your life where a solid state changes directly to a gaseous state or a gaseous state changes directly to a solid state?

Sublimation: The process of matter changing directly from solid to gaseous state is called sublimation.

Sublimation: The process of changing directly from gaseous state to solid state is called sublimation.

Think about it: there are other examples of sublimation and sublimation in life.

Let’s talk about: the role of material sublimation and condensation.

Discussion: Why do the glass walls of ordinary light bulbs and fluorescent lamps turn black after being used for a long time?

Dew occurs when the water vapor in the air encounters cooler leaves, flowers and plants before early morning when the weather is hot, and liquefies into small water droplets that adhere to their surfaces. This is a liquefaction phenomenon.

The situation of fog and clouds is the same. Both water vapor liquefies into small water droplets when it is cooled in the air. These small water droplets are suspended in the air and are called fog near the ground. They are called clouds at high altitudes. Therefore, fog and clouds They are all phenomena of liquefaction of water vapor, not sublimation of ice.

Frost is when water vapor on the ground surface condenses directly into a solid when it encounters temperatures below zero degrees Celsius.

Snow occurs when the weather is cold and the temperature in the air is below zero degrees Celsius. Water vapor condenses into solid state in the air and becomes hexagonal ice crystals (called snowflakes). They combine with each other to form snow flakes or snow clumps as they fall.

Summary: seven threes

1. Three states: ① solid state, ② liquid state, ③ gas state

2. Three endothermic processes: ① melting, ② vaporization, ③ sublimation

3. Three exothermic processes: ① Solidification, ② Liquefaction, ③ Sublimation

4. Three reciprocal processes: ① Melting and solidification, ② Vaporization and liquefaction, ③ Sublimation and sublimation

5. Three special (temperature) points: ① Melting point: the temperature when the crystal melts; ② Freezing point: the temperature when the crystal solidifies: ③ Boiling point: the temperature when the liquid boils.

6. Three constant temperatures: ① The temperature when the crystal melts; ② The temperature when the crystal solidifies; ③ The temperature when the liquid boils.

7. Three conditions: ① Necessary and sufficient conditions for crystal melting: reaching the melting point; continuing to absorb heat; and the temperature remaining unchanged. ② Necessary and sufficient conditions for crystal solidification: reaching the freezing point; continuing to release heat; and the temperature remaining unchanged. ③Necessary and sufficient conditions for liquid to boil: reach boiling point; continue to absorb heat; temperature remains unchanged.

Keywords: teaching courseware of sublimation and sublimation, teaching courseware of states of matter and its changes, Beijing Normal University version eighth grade physics PPT courseware download, eighth grade physics slide courseware download, download of sublimation and sublimation PPT courseware, states of matter and their changes Change PPT courseware download, .PPT format;

For more information about the "Sublimation and Sublimation States of Matter and Their Changes" PPT courseware, please click the Sublimation and Sublimation ppt State of Matter and its Changes ppt tag.

"Sublimation and Sublimation" Material Forms and Changes PPT Courseware 3:

"Sublimation and Sublimation" Material Forms and Changes PPT Courseware 3 Review Review 1. What are the conversion processes between solid and liquid called? Endothermic or exothermic? The change of matter from solid to liquid is called melting, which is an endothermic process. ; The change of substance from liquid to solid is called solidification..

"Sublimation and Sublimation" Material Form and Its Changes PPT Courseware 2:

"Sublimation and Sublimation" Material Forms and Changes PPT Courseware 2 Learning Objectives 1. Know what sublimation and sublimation are, and understand the phenomena of sublimation and sublimation in life 2. Know that sublimation absorbs heat and sublimation releases heat 3. I am willing to explore the phenomena of sublimation and sublimation in life and appreciate...

"Sublimation and Sublimation" Material Forms and Changes PPT Courseware:

"Sublimation and Sublimation" Material Forms and Changes PPT Courseware Teaching Objectives 1. Know what sublimation and sublimation are, and understand the phenomena of sublimation and sublimation in life. 2. Know that sublimation needs to absorb heat and sublimation needs to release heat. 3. Understand and sublimate through experiments, observation and analysis..

File Info

Update Time: 2024-08-01

This template belongs to Physics courseware Beijing Normal University eighth grade physics volume one industry PPT template

Preview