What happens to the molecules of a substance when the substance is in different states of aggregation? what is the speed of the molecules of the substance? what is the distance between. Presentation for the lesson "melting"

What happens to the molecules of a substance when the substance is in different states of aggregation? what is the speed of the molecules of the substance? what is the distance between molecules? what is the arrangement of molecules? gas liquid solid body The transition of a substance from a solid to a liquid state is called melting The body is given energy How does the internal energy of a substance change? How does the energy of molecules and their arrangement change? When will the body begin to melt? Do the molecules of a substance change when melted? How does the temperature of a substance change during melting? The transition of a substance from a liquid state to a solid state is called crystallization. The liquid gives off energy. How does the internal energy of a substance change? How does the energy of molecules and their arrangement change? When will the body begin to crystallize? Do the molecules of a substance change during crystallization? How does the temperature of a substance change during crystallization? Physical quantity, showing how much heat is needed to convert 1 kg crystalline substance, taken at the melting temperature, into a liquid of the same temperature, is called the specific heat of fusion Designated: t , C t3 t2  Absorption Q Unit of measure: J kg Emission Q Q   m Q    m melting solidification t , min t1 melting t = solidification t “Reading the graph” Which sections of the section Describe the graph Which transformation graph corresponds to the initial increase in temperature with the internal state of the substance? substances? matter energy? decrease? substances to decrease? 1 3 2 4 “Reading the graph” At what point in time did the process of melting of the substance begin? At what point in time did the substance crystallize? What is the melting point of the substance? crystallization? How long did it take: heating solid body ; melting of a substance; liquid cooling? Check yourself! 1. When a body melts ... a) heat can be both absorbed and released. b) heat is neither absorbed nor released. c) heat is absorbed. d) heat is released. 2. When a liquid crystallizes ... a) the temperature can both rise and fall. b) the temperature does not change. c) the temperature goes down. d) the temperature rises. 3. When a crystalline body melts ... a) the temperature decreases. b) the temperature can both rise and fall. c) the temperature does not change. d) the temperature rises. 4. During aggregate transformations of a substance, the number of molecules of a substance ... a) does not change. b) can both increase and decrease. c) decreases. d) is increasing. Answer: 1-c 2-b 3-c 4-a The transition of a substance from a liquid state to a gaseous state is called vaporization How does the internal energy of a substance change during vaporization? How does the energy of molecules and their arrangement change? Do the molecules of a substance change during vaporization? How does the temperature of a substance change during vaporization? The transition of a substance from a gaseous state to a liquid state is called condensation. How does the internal energy of a substance change during condensation? How does the energy of molecules and their arrangement change? Do the molecules of a substance change during condensation? Evaporation - vaporization occurring from the surface of a liquid 1. What molecules leave the liquid during evaporation? 2. How does the internal energy of a liquid change during evaporation? 3. At what temperature can evaporation occur? 4. How does the mass of a liquid change during evaporation? Explain why: did the water from the saucer evaporate faster? off balance? after a few days, the levels of different fluids became different. Explain how will evaporation occur if the wind blows over the liquid? Why does water evaporate faster from a plate than from a bowl? boiling 1. What is formed on the walls of the jar if it has been standing with water for a long time? 2. What is in these bubbles? 3. The surface of the bubbles is also the surface of the liquid. What will happen to the surface inside the bubbles? boiling Compare the processes of evaporation and boiling evaporation boiling 1. In what part of the liquid does vaporization occur? 2. What changes in liquid temperature occur during vaporization? 3. How does the internal energy of a liquid change during vaporization? 4. What determines the speed of the process? The work of gas and steam during expansion 1. Why does the lid of the kettle sometimes bounce when water boils in it? 2. When the steam pushes the lid of the kettle, what does it do? 3. What energy transformations take place when the lid bounces? ICE Hot Ice We are accustomed to believe that water cannot be in a solid state at t above 0 0C. The English physicist Bridgman showed that water under pressure p ~ 2*109 Pa remains solid even at t = 76 0C. This is the so-called "hot ice - 5". You can’t pick it up; you learned about the properties of this type of ice indirectly. "Hot ice" is denser than water (1050 kg/m3), it sinks in water. Today, more than 10 varieties of ice with amazing qualities are known. Dry ice When burning coal, you can get not heat, but, on the contrary, cold. To do this, coal is burned in boilers, the resulting smoke is cleaned and trapped in it. carbon dioxide. It is cooled and compressed to a pressure of 7*106 Pa. It turns out liquid carbon dioxide. It is stored in thick-walled cylinders. When the tap is opened, liquid carbon dioxide expands sharply and cools, turning into solid carbon dioxide - “dry ice”. Under the influence of heat, dry ice flakes immediately turn into a gas, bypassing the liquid state.

What happens to the molecules of a substance when the substance
is in different aggregate states?
what is the speed of the molecules of the substance?
what is the distance between molecules?
what is the arrangement of molecules?

gas
liquid

solid
body

The transition of a substance from solid to liquid
called melting
The body is given energy
substances?
them
location?
When will the body begin to melt?
when melting?
when melting?

The transition of a substance from liquid to solid
called crystallization
liquid gives off energy
How does internal energy change
substances?
location?
When will the body begin to crystallize?
Do the molecules of matter change?
during crystallization?
How does the temperature of a substance change?
during crystallization?

Physical quantity showing how much heat
necessary for the transformation of 1 kg of a crystalline substance taken
at the melting point, into a liquid of the same temperature, is called
specific heat of fusion

Unit of measurement:
J
kg
Designated:
, tC
3t
2t
1t
Q absorption
Q selection
m
Q
melting
m
Q
hardening
the heating
melting t = solidification t
about
X
l
a
and
d
, tmin
e
n
and
e

"Reading the chart"
Which section of the graph corresponds to the increase in internal energy
Which parts of the graph correspond to the temperature increase
Describe the initial state
What transformations take place in matter?
substances? decrease?
substances? decrease?
substances
1
3
2
4

"Reading the chart"
At what point in time did the melting process begin?
At what point in time did the substance crystallize?
What is the melting point of the substance? crystallization?
How long did it take: heating a solid body;
melting of a substance;
liquid cooling?

Check yourself!
1. When melting the body...
a) heat can be both absorbed and released.
b) heat is neither absorbed nor released.
c) heat is absorbed.
d) heat is released.
2. When liquid crystallizes...
a) The temperature can both rise and fall.
b) the temperature does not change.
c) the temperature goes down.
d) the temperature rises.
3. When melting a crystalline body...
a) the temperature goes down.
b) the temperature can both rise and fall.
c) the temperature does not change.
d) the temperature rises.
4. During aggregate transformations of a substance, the number of molecules of a substance ...
a) does not change.
b) can both increase and decrease.
c) decreases.
d) is increasing.
Answer: 1c 2b 3c 4a

The transition of a substance from a liquid state to
gaseous is called vaporization
How does internal energy change
substances during vaporization?
How does the energy of molecules change?
their location?
Do the molecules of matter change?
during vaporization?
How does the temperature change
substances during vaporization?

The transition of a substance from a gaseous state to a liquid
called condensation
How does internal energy change
substances in condensation?
How does the energy of molecules change?
their location?
Do the molecules of matter change?
during condensation?

Evaporation - vaporization
coming from the surface of the liquid
1. What molecules leave the liquid
during evaporation?
2. How internal energy changes
evaporation liquid?
3. At what temperature can
evaporation occur?
4. How does the mass of liquid change with
evaporation?

Explain why:
Did the water from the saucer evaporate faster?
off balance?
after a few days the level of various
liquids became different.

explain
How will evaporation occur if
Will the wind blow over the liquid?
Why does water evaporate faster from a plate than from a bowl?

boiling
1. What is formed on the walls of the jar, if it
How long did you stand with water?
2. What is in these bubbles?
3. Bubble surface at the same time
is the surface of the liquid. What will happen
come from the surface inside the bubbles?
boiling

Hot Ice
We tend to think that water
cannot be solid
at t above 0 0С.
English physicist Bridgman
said that pressurized water p ~
2*109 Pa remains solid even when
t = 76 0С. This is the so-called "
hot ice 5". Do not take it in hand
lzya, about the properties of this variety
sti ice learned indirectly.
"Hot ice" is denser than water (1050
kg/m3), it sinks in water.
Today, more than 10 different
views of ice with amazing
qualities.
Dry ice
When coal is burned, it is possible to
Chit not heat, but rather cold. For
this coal is burned in boilers,
the resulting smoke is cleaned and
capture carbon dioxide in it.
It is cooled and compressed to
pressure 7*106 Pa. It turns out
liquid carbon dioxide. She is kept in
thick-walled cylinders.
When the tap is opened, the liquid
carbon dioxide expands and
cools down, turning into solid
I blow carbon dioxide - "dry ice".
Influenced by heat flakes
dry ice immediately turn into gas,
bypassing the liquid state.

A very high-quality presentation for schoolchildren (grade 7) studying physics on the topic "Change state of aggregation substances". Presentation format - powerpoint. Contains 17 slides with illustrations.

• What happens to the molecules of a substance when the substance is in different states of aggregation?
• what is the speed of the molecules of the substance?
• what is the distance between molecules?
• what is the arrangement of molecules?

Melting

• How the energy of molecules and their arrangement changes
• When will the body begin to melt?
• Do the molecules of a substance change when melted?
• How does the temperature of a substance change during melting?

crystallization

• How does the internal energy of matter change?
• When will the body begin to crystallize?
• Do the molecules of a substance change during crystallization?
• How does the temperature of a substance change during crystallization?

The melting temperature is equal to the solidification temperature.

Reading the chart:

• At what point in time did the melting process begin?
• At what point in time did the substance crystallize?
• What is the melting point of the substance? crystallization?
• How long did it take: heating a solid body; melting of a substance; liquid cooling?

1. When melting the body...

1. Heat can be both absorbed and released.
2. heat is neither absorbed nor released.
3. heat is absorbed.
4. heat is released.

• temperature does not change.
• the temperature goes down.
• the temperature rises.

1. the temperature goes down.
2. The temperature can both rise and fall.
3. temperature does not change.
4. the temperature rises.

1. does not change.
2. can both increase and decrease.
3. decreases.
4. increases.

vaporization

• How does the internal energy of a substance change during vaporization?
• How does the energy of molecules and their arrangement change?
• Do the molecules of a substance change during vaporization?
• How does the temperature of a substance change during vaporization?

Condensation

• How does the internal energy of a substance change during condensation?
• How does the energy of molecules and their arrangement change?
• Do the molecules of a substance change during condensation?

Evaporation

• What molecules leave the liquid during evaporation?
• How does the internal energy of a liquid change during evaporation?
• At what temperature can evaporation occur?
• How does the mass of a liquid change during evaporation?

Boiling

• What is formed on the walls of the jar if it has been standing with water for a long time?
• What is in these bubbles?
• The surface of the bubbles is also the surface of the liquid. What will happen to the surface inside the bubbles?

• In what part of the liquid does vaporization take place?
• What changes in liquid temperature occur during vaporization?
• How does the internal energy of a liquid change during vaporization?
• What determines the speed of the process?

The work of gas and steam during expansion.

• Why does the lid of the kettle sometimes bounce when water boils in it?
• When the steam pushes the lid of the kettle, what does it do?
• What energy transformations take place when the lid bounces?

Hot Ice

The English physicist Bridgman showed that water under pressure p ~ 2000 MPa remains solid even at t = 76 degrees Celsius. This is the so-called "hot ice". You can’t pick it up; you learned about the properties of this type of ice indirectly.

"Hot ice" is denser than water (1050 kg/m3), it sinks in water. Today, more than 10 varieties of ice with amazing qualities are known.

Dry ice

When burning coal, you can get not heat, but, on the contrary, cold. To do this, coal is burned in boilers, the resulting smoke is cleaned and carbon dioxide is captured in it. It is cooled and compressed to a pressure of 7*106 Pa. It turns out liquid carbon dioxide. It is stored in thick-walled cylinders.

When the tap is opened, liquid carbon dioxide expands sharply and cools, turning into solid carbon dioxide - “dry ice”. Under the influence of heat, dry ice flakes immediately turn into a gas, bypassing the liquid state.

What happens to the molecules of a substance when the substance is in different states of aggregation?

what is the speed of the molecules of the substance?

what is the distance between molecules?

what is the arrangement of molecules?

gas

liquid

solid

The transition of a substance from a solid state to a liquid state is called melting.

The body is given energy

When will the body begin to melt?

Do the molecules of a substance change when melted?

How does the temperature of a substance change during melting?

The transition of a substance from a liquid state to a solid state is called crystallization

liquid gives off energy

How does the internal energy of matter change?

How does the energy of molecules and their arrangement change?

When will the body begin to crystallize?

Do the molecules of a substance change during crystallization?

How does the temperature of a substance change during crystallization?

"Reading the chart"

Which part of the graph Ox graph which acterize transforming corresponds to corresponding initially to growth go to a certain temperature of the early state of the substance? energy of the substance? of the substance? decrease? substances?

"Aggregate state of matter" - Condensation Crystallization. Vaporization. Content. Tcrystallization = tmelting. Aggregate states of matter. Graph of the processes of changing the state of aggregation of matter. Water heating. Water cooling. Melting. Ice heating. Three states of matter. Tmelt=const. Processes with absorption and release of heat.

"Test "Thermal phenomena"" - The phenomenon of heat transfer. History of tea. Examination. Mistress of the house. Ancient aphorism. Convection. Heating curve of a crystalline substance. Cooling of a solid body. Let's start the story about warmth. What method of heat transfer allows you to warm yourself by the fireplace. Visual gymnastics. Research work.

“Substance and its state” - Even steel steam above it is observed then. They take the form of a vessel, Oxygen can be solid, Liquid can also be. In states of aggregation, water will always show us different properties. They don't have their own. The whole world is made up of molecules! Liquid, Solid, Molecule - smallest particle substances. Shape and permanent.

"3 states of matter" - Substance. Crystallization. Ice. Process examples. Vaporization. states. Arrangement of molecules in liquids. Solve the crossword. Condensation. Character of movement and interaction of particles. Arrangement of molecules in gases. Interesting Facts. Properties of liquids. Questions for the crossword. Properties of solid bodies. Change physical properties substances.

"Three States of Matter" - Solid. Physics grade 7. Why do solids keep their shape? Three states of matter. What causes an increase in the temperature of a solid? What can be said about the arrangement of molecules when water is heated to a boil? The water evaporated and turned into steam. Questions: Can an open vessel be filled with gas by 50%?

"Thermal phenomena grade 8" - 2. It's not clear why ...? The moon shines, but does not warm? Do you know how a person takes into account thermal phenomena in everyday life? Have you thought about the question: why modern home live comfortably? Is mom right when she calls her child “You are my sun”? Thermal phenomena in your house. Is it hot in black clothes in summer?