"Melting and Solidification" PPT

Description

"Melting and Solidification" PPT

Part One: Status Changes

Solid, liquid, and gas are the three common states of matter.

Solid state: such as aluminum, gold, silver, copper, iron, etc. are usually solid

Liquid: such as water, vinegar, oil, etc. are usually liquid

Gaseous state: such as oxygen, hydrogen, nitrogen, etc. are usually in gaseous state

Melting – The process of a substance changing from a solid state to a liquid state is called melting.

Solidification - The process of a substance changing from a liquid to a solid state is called solidification.

Melting and Solidification PPT, Part 2: Conclusion

Melting point - the temperature at which a crystal melts

Solid matter classification

Crystal: An object with a certain melting temperature

Amorphous: an object that does not have a certain melting temperature

Crystalline and amorphous melting laws

1. The temperature does not change when crystals melt; the temperature of amorphous crystals always increases during the melting process.

2. During the crystal melting process, solid and liquid coexist; amorphous melting is a softening process.

3. Both crystals and amorphous crystals absorb heat when melting.

Conditions for crystal melting: ① The temperature reaches the melting point ② It needs to continue to absorb heat

Melting and solidification PPT, Part 3: Laws of crystal solidification

1. Solidification is the reverse process of melting.

2. The temperature of the crystal does not change during the solidification process. This temperature is called the freezing point.

3. During the solidification process, solid and liquid coexist;

4. The crystal only begins to solidify when it reaches a certain temperature;

5. The solidification process releases heat.

Melting and solidification PPT, Part 4 content: Classroom exercises:

1. During the science review class, the teacher wrote a couplet. The first couplet is "Ice water in the cup, the temperature of the water does not drop when it freezes"; the second couplet is "There is ice in the dish, but the temperature of the ice does not rise". The material changes contained in the couplet are ______ and ______, reflecting the commonality of ______.

2. Can crystals melt as long as the temperature reaches the melting point?

Although the temperature of the crystal remains unchanged during the melting process, it must continue to be heated for the melting process to be completed, which shows that the crystal also absorbs heat during the melting process, and the amorphous crystal also absorbs heat during the melting process, but the temperature changes.

Melting and Solidification PPT, Part 5: Class Summary

According to the different melting characteristics of solids, solids can be divided into two categories: ______ and ______; one very important difference between them is ______

The conditions for crystal melting are ___________, the temperature during the melting process _______, and the temperature during the melting process for amorphous crystals is ______. The freezing point of the same substance is the same as its ____

Keywords: Zhejiang Education Edition seventh grade science PPT courseware free download, melting and solidification PPT download, .PPT format;

For more information about the "Melting and Solidification" PPT courseware, please click the Melting and Solidification ppt tab.

"Melting and Solidification" PPT courseware:

Contents of the first part of the PPT courseware "Melt and Solidify": Three states of matter: Take water as an example: ice rain, white gas, fog, dew, frost, snow, hail Water vapor Solid state: ice, frost, snow and hail Liquid state: rain, fog, dew, white gas Gaseous state: water Vapor (invisible to the human eye) ... ...

"Exploring the Characteristics of Melting and Solidification" Material Forms and Their Changes PPT Courseware 2:

"Exploring the Characteristics of Melting and Solidification" Material Form and Its Changes PPT Courseware 2 Learning Objectives 1. Know what melting and solidification are. Understand the endotherms of melting and the exotherms of solidification. Know the characteristics of crystalline and amorphous melting and solidification. Understand the physical meaning of melting curves. 2. know..

"Exploring the Characteristics of Melting and Solidification" Material Forms and Their Changes PPT Courseware:

"Exploring the Characteristics of Melting and Solidification" Material Forms and Changes PPT Courseware Teaching Objectives 1. Know what melting and solidification are, and understand the heat absorption of melting and the heat release of solidification. 2. Know the melting and solidification characteristics of crystals and amorphous crystals. Understand the physical meaning of melting curves. ..

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Update Time: 2024-07-30

This template belongs to science courseware Zhejiang Education Edition Seventh Grade Science Volume 1 industry PPT template

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