Solving the problem of physical state change in the second day of junior high school

Physics "state change" unit examination paper of the second day of junior high school.

Name score

First, multiple-choice questions (20 * 2' = 40')

1, belongs to the liquefaction phenomenon in the following phenomenon is ()

A. Ice cubes added to drinks will turn into water B. Wet clothes dried in the sun.

C. "white gas" appears around the popsicle just taken out of the refrigerator. D. White "frost" appears on the inner wall of the freezer.

2, the following natural phenomena, belongs to the melting phenomenon is ()

A. In spring, the ice in the river turns into water. B. In the early morning of summer, dew adheres to the leaves of flowers and plants.

C. In the autumn morning, fog covers the earth. In winter, snowflakes fly in the air.

3. Among the following statements, what do you think is the most practical one ()?

A. The normal body temperature is 35℃. The temperature of the freezer is about 5℃.

C. In Shanghai in midsummer, the outdoor temperature can reach 38℃ at noon. D. The lowest temperature in Shanghai can reach -30℃.

4. "misty fog, crystal dew, dignified frost, gentle snow and the same water molecules dress up the time and space of our lives." This is a lyric poem describing physical phenomena. The correct understanding of the physical phenomenon described in this poem is ()

A. "Mist" is a vaporization phenomenon. B. "Crystal dew" is a liquefaction phenomenon.

C. "dignified frost" is a solidification phenomenon D. "soft snow" is a melting phenomenon

5, in the process of the formation of the following phenomena, a group that absorbs heat is ()

(1) in spring, ice and snow melt into streams; ② In summer, water pipes "sweat".

In autumn, dew condenses on the grass. In winter, frozen clothes will be dried.

A.①② B.②③ C.①④ D.③④

6. After lunch, Xiao Ming and Xiao Ling came to the store. Xiaoming bought a popsicle and Xiaoling bought a lollipop. When they put popsicles and lollipops in their mouths, they all slowly disappeared. The following description of this change is correct ()

A, popsicles melt, lollipops melt. B, the popsicle is melted and the lollipop is melted.

C, "popsicles" and "lollipops" have all melted. D. "Popsicle" and "lollipop" were dissolved.

7, the table below is the melting point and boiling point of some substances (standard atmospheric pressure), according to the table below, the thermometer can measure temperature in all parts of our country is ().

A. Water thermometer B. Alcohol thermometer

C. mercury thermometer ether thermometer

8. A memorial bronze statue should be cast in the memorial hall. In the process of casting bronze statue with copper block, the state change of copper block is ().

A. sublimation first, then sublimation B. sublimation first, then sublimation

C, melting first, then curing d, curing first, then melting.

9. The picture on the right shows the temperature change with time when the material melts. The information given by the image,

The following judgment is correct ()

A. The melting point of this substance is 0℃, and it is in a solid-liquid state from the second minute to the third minute, so the internal energy can be increased.

B The melting point of this substance is 0℃, and it is in a solid-liquid state from the second minute to the third minute, and its internal energy remains unchanged.

C. The melting point of this substance is -4℃, and it is liquid within 5 to 6 minutes, so the internal energy is increased.

D. The melting point of this substance is 0℃, and it is gaseous within the fifth to sixth 56 minutes, so the internal energy can be increased.

10, the following natural phenomena, belong to ninghua is ()

A. In the morning of late autumn, the fog is filled. B. In the morning of winter, frost hits the branches.

C.in spring, the ice and snow in the river melt. D. In the summer morning, dew adheres to flowers and plants.

1 1, Tibet has a high altitude. Regarding the pressure and boiling point of water in Tibet, the following statement is true ()

A. Low air pressure and high boiling point of water B. High air pressure and high boiling point of water.

C. Low air pressure and low boiling point of water D. High air pressure and low boiling point of water.

12, alcohol thermometer and kerosene thermometer can measure different maximum temperatures, which is mainly due to the () of alcohol and kerosene.

A. different boiling point B. different freezing point C. different specific heat capacity D. different density

13, Mao Zedong Snow, a great man in Qinyuanchun, wrote: "The scenery in the north is frozen for thousands of miles, and the snow in Wan Li floats". The main physical change that forms this natural scene is ().

A. Melting and vaporization B. Solidification and sublimation C. Solidification and liquefaction D. Vaporization and sublimation

14, if you want to cook in the mountains, the method you can take is ().

A. reduce heating time B. reduce firepower C. pressure cooker D. open cover cooking.

15, a pot of boiling oil, the magician puts his hand in, one minute, two minutes ... and then takes it out-nothing! The analysis of this phenomenon is correct ()

One, this is impossible, this is pseudoscience.

B, it's impossible. The temperature keeps rising when the oil is boiling.

C, this is possible. It must be that the boiling point of this oil is very low.

D, this is possible, there must be water on hand, and water absorbs heat from oil.

16. There were many artistic and scientific drinking vessels in ancient China. There is a kind of cup called "Chang Man Cup" with a cone made of fine white jade. When it is placed in the air, it constantly produces water droplets, so that it is always full. About this cup, the following statement is wrong ()

A, the water in the cup is formed by the liquefaction of water vapor on white jade.

B, the water in the cup is formed by air liquefaction on white jade.

C. White jade is a substance with small specific heat, and the temperature changes significantly under the same conditions.

D, cups can automatically "generate" water in water-deficient mountainous areas.

17, the following measures, in order to speed up the evaporation is ()

A. When the alcohol lamp is not used, cover the lamp cap. B spread out the wet clothes and hang them in a sunny and ventilated place.

C, putting the fresh-keeping bagged vegetables into the refrigerator d, and cutting off a large number of branches and leaves when planting trees in spring.

18. In order to manufacture a special steel-aluminum can, the inner surface of the steel can needs to be pressed with 0.25mm thick aluminum film, which stumped the welding and forging experts for a while. Later technicians jointly solved this problem: they first stuck the aluminum film on the inner surface of the steel tank, then filled the steel tank with water, inserted a freezing pipe to freeze the water, and then pressed the aluminum film and the steel tank together. The reason is ()

A the water between the aluminum film and the steel can will freeze them firmly. B the ice between the aluminum film and the steel can will stick them together firmly when it freezes.

C. when water freezes, the huge pressure generated by expansion presses them tightly. The heat released when water freezes will weld them firmly together.

19. After the metal block was frozen in the refrigerator, it was taken out for a while and found to be wet. Wipe it with a dry towel, and the metal block is wet again. The reason is ()

A, the water absorbed by the metal block in the refrigerator continues to permeate outward.

B, the water vapor in the air liquefies into water and adheres to the surface of the metal block.

C water in the air adheres to the surface of the metal block.

D, the water in the air is vaporized into water vapor and attached to the surface of the metal block.

20, the following statement, the correct is ()

A. heat the ice, and the temperature of the ice will definitely rise.

B put water at 5℃ into a room at 0℃, and it will freeze.

The "white gas" around the C popsicle is water vapor formed by ice sublimation.

D outdoor water pipes are easy to freeze and crack in winter, because the volume of water becomes larger after freezing.

Fill in the blanks (20 * 1' = 20')

1. In order to make rational use of resources, Xiao Ming put forward the following ideas: making ice by using the electric energy with low electricity consumption at night in summer, and cooling the room by using the heat absorption of ice during the day (fill in the name of material state change); The principle of thermometer is.

There is physics everywhere in life, and you can learn it by careful observation. Do you know that?/You know what? The kitchen also contains a lot of physical knowledge. For example, holding steamed bread that has just come out of the cage and touching some cold water on your hands won't feel very hot. This is because _ _ _ _ _.

3. Please write down the name of the state change to which the following phenomena belong: eating popsicles in summer will give off "white steam" after opening the wrapping paper _ _ _ _ _ _ _; Dry wet hands with a hot air hand dryer _ _ _ _ _; Long-used bulb tungsten filament is thinner than when it was new _ _ _ _?

4. In the summer morning, there are often crystal dewdrops on outdoor flowers and leaves, which is a phenomenon; In the cold winter, when I get up in the morning, I often see a layer of white ice flowers on the window, which is a phenomenon.

5. Put your hands in hot water and cold water at the same time. After a period of time, take out your hands and put them in warm water at the same time. The feeling of hands at this time (choose "same" or "different"). This fact shows that.

6. During the boiling process of water, the temperature of water _ (optional "increase", "decrease" or "unchanged") and process water (optional "endothermic", "exothermic" or "neither endothermic nor exothermic"). At standard atmospheric pressure, the melting point of alcohol is-1 17℃ and the boiling point is 78. The melting point of mercury is -39℃ and the boiling point is 357℃. Do you think _ (choose "alcohol" or "mercury") thermometer should be used to measure the temperature of boiling water? Liquid thermometer uses the characteristics of liquid to measure temperature.

7. The melting points and boiling points of several substances are shown in the table below, so lead is in the state of _ _ _ _ _ _ _ _ _ _ at 300℃, mercury is in the state of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ at 350℃, and alcohol is in the state of _ _ _ _ _ _ _ _ _ at 80℃. It is cold in northern China, so it should be chosen as the temperature measuring liquid.

Material melting point (℃) boiling point (℃)

Clue 328 1740

Mercury 38.8 357

Alcohol-1 1778.5

8. By observing the three schematic diagrams of clothes drying shown in Figure 4, combined with the experience of daily life, we can know that the evaporation speed of liquid is related to the air velocity of liquid, liquid and liquid surface.

Third, the experimental questions

1, wave is crystal, paraffin is amorphous. The melting image of sea waves and paraffin wax collected by Xiaohua through consulting the data is shown in the figure, and the melting image of sea waves is _ _ _ _ _ (fill in the serial number).

The information that can be obtained by analyzing the field is as follows:

①____________________________

②_____________________________

Information that can be obtained by analyzing image b is as follows:

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

2. In order to study the boiling of water, Xiaowen observed the change of water temperature with heating time during heating, and recorded the relevant data in the following table:

Time/Minute 0 1 2 3 4 5 6 7 8 9

Temperature/℃

(1) Please draw points in Figure 12 according to the recorded data, and then use a smooth.

The curve shows the image of water boiling.

(2) According to the image, the heating process of water has the following characteristics:

(Write only 3 points)

① ;

② ;

③ .

3. From June 10 to June 16, 2003, China successfully launched and recovered Shenzhou 5's manned spacecraft.

(1) When the rocket was launched, the high-temperature flame sprayed downward, and a large amount of "white gas" gushed out from the large pool at the bottom of the launch pad. How are these "white gases" formed?

(2) When the return capsule passes through the atmosphere, it rubs with air to generate heat, and the surface of the return capsule is very hot. However, due to the very thick special coating on the surface of the return capsule, the temperature in the capsule remained normal, so some physical changes occurred. Please explain the working principle of volatile coatings.

Liu Juan often helps her mother do housework in her spare time. She killed mosquitoes in her room once, using aerosol insecticide, as shown in the picture. Liu Juan sprayed it with this insecticide-after a while, her hands obviously felt that the metal can with the insecticide was getting cold. She shook the metal can and obviously felt the liquid in it. She learned from reading the instructions that this pesticide is made of a highly volatile chemical raw material and medicine. Please use your physical knowledge to explain why the metal can is cold.

Physics "state change" unit examination paper of the second day of junior high school.

Name score

First, multiple-choice questions (20 * 2' = 40')

1, belongs to the liquefaction phenomenon in the following phenomenon is ()

A. Ice cubes added to drinks will turn into water B. Wet clothes dried in the sun.

C. "white gas" appears around the popsicle just taken out of the refrigerator. D. White "frost" appears on the inner wall of the freezer.

2, the following natural phenomena, belongs to the melting phenomenon is ()

A. In spring, the ice in the river turns into water. B. In the early morning of summer, dew adheres to the leaves of flowers and plants.

C. In the autumn morning, fog covers the earth. In winter, snowflakes fly in the air.

3. Among the following statements, what do you think is the most practical one ()?

A. The normal body temperature is 35℃. The temperature of the freezer is about 5℃.

C. In Shanghai in midsummer, the outdoor temperature can reach 38℃ at noon. D. The lowest temperature in Shanghai can reach -30℃.

4. "misty fog, crystal dew, dignified frost, gentle snow and the same water molecules dress up the time and space of our lives." This is a lyric poem describing physical phenomena. The correct understanding of the physical phenomenon described in this poem is ()

A. "Mist" is a vaporization phenomenon. B. "Crystal dew" is a liquefaction phenomenon.

C. "dignified frost" is a solidification phenomenon D. "soft snow" is a melting phenomenon

5, in the process of the formation of the following phenomena, a group that absorbs heat is ()

(1) in spring, ice and snow melt into streams; ② In summer, water pipes "sweat".

In autumn, dew condenses on the grass. In winter, frozen clothes will be dried.

A.①② B.②③ C.①④ D.③④

6. After lunch, Xiao Ming and Xiao Ling came to the store. Xiaoming bought a popsicle and Xiaoling bought a lollipop. When they put popsicles and lollipops in their mouths, they all slowly disappeared. The following description of this change is correct ()

A, popsicles melt, lollipops melt. B, the popsicle is melted and the lollipop is melted.

C, "popsicles" and "lollipops" have all melted. D. "Popsicle" and "lollipop" were dissolved.

7, the table below is the melting point and boiling point of some substances (standard atmospheric pressure), according to the table below, the thermometer can measure temperature in all parts of our country is ().

A. Water thermometer B. Alcohol thermometer

C. mercury thermometer ether thermometer

8. A memorial bronze statue should be cast in the memorial hall. In the process of casting bronze statue with copper block, the state change of copper block is ().

A. sublimation first, then sublimation B. sublimation first, then sublimation

C, melting first, then curing d, curing first, then melting.

9. The picture on the right shows the temperature change with time when the material melts. The information given by the image,

The following judgment is correct ()

A. The melting point of this substance is 0℃, and it is in a solid-liquid state from the second minute to the third minute, so the internal energy can be increased.

B The melting point of this substance is 0℃, and it is in a solid-liquid state from the second minute to the third minute, and its internal energy remains unchanged.

C. The melting point of this substance is -4℃, and it is liquid within 5 to 6 minutes, so the internal energy is increased.

D. The melting point of this substance is 0℃, and it is gaseous within the fifth to sixth 56 minutes, so the internal energy can be increased.

10, the following natural phenomena, belong to ninghua is ()

A. In the morning of late autumn, the fog is filled. B. In the morning of winter, frost hits the branches.

C.in spring, the ice and snow in the river melt. D. In the summer morning, dew adheres to flowers and plants.

1 1, Tibet has a high altitude. Regarding the pressure and boiling point of water in Tibet, the following statement is true ()

A. Low air pressure and high boiling point of water B. High air pressure and high boiling point of water.

C. Low air pressure and low boiling point of water D. High air pressure and low boiling point of water.

12, alcohol thermometer and kerosene thermometer can measure different maximum temperatures, which is mainly due to the () of alcohol and kerosene.

A. different boiling point B. different freezing point C. different specific heat capacity D. different density

13, Mao Zedong Snow, a great man in Qinyuanchun, wrote: "The scenery in the north is frozen for thousands of miles, and the snow in Wan Li floats". The main physical change that forms this natural scene is ().

A. Melting and vaporization B. Solidification and sublimation C. Solidification and liquefaction D. Vaporization and sublimation

14, if you want to cook in the mountains, the method you can take is ().

A. reduce heating time B. reduce firepower C. pressure cooker D. open cover cooking.

15, a pot of boiling oil, the magician puts his hand in, one minute, two minutes ... and then takes it out-nothing! The analysis of this phenomenon is correct ()

One, this is impossible, this is pseudoscience.

B, it's impossible. The temperature keeps rising when the oil is boiling.

C, this is possible. It must be that the boiling point of this oil is very low.

D, this is possible, there must be water on hand, and water absorbs heat from oil.

16. There were many artistic and scientific drinking vessels in ancient China. There is a kind of cup called "Chang Man Cup" with a cone made of fine white jade. When it is placed in the air, it constantly produces water droplets, so that it is always full. About this cup, the following statement is wrong ()

A, the water in the cup is formed by the liquefaction of water vapor on white jade.

B, the water in the cup is formed by air liquefaction on white jade.

C. White jade is a substance with small specific heat, and the temperature changes significantly under the same conditions.

D, cups can automatically "generate" water in water-deficient mountainous areas.

17, the following measures, in order to speed up the evaporation is ()

A. When the alcohol lamp is not used, cover the lamp cap. B spread out the wet clothes and hang them in a sunny and ventilated place.

C, putting the fresh-keeping bagged vegetables into the refrigerator d, and cutting off a large number of branches and leaves when planting trees in spring.

18. In order to manufacture a special steel-aluminum can, the inner surface of the steel can needs to be pressed with 0.25mm thick aluminum film, which stumped the welding and forging experts for a while. Later technicians jointly solved this problem: they first stuck the aluminum film on the inner surface of the steel tank, then filled the steel tank with water, inserted a freezing pipe to freeze the water, and then pressed the aluminum film and the steel tank together. The reason is ()

A the water between the aluminum film and the steel can will freeze them firmly. B the ice between the aluminum film and the steel can will stick them together firmly when it freezes.

C. when water freezes, the huge pressure generated by expansion presses them tightly. The heat released when water freezes will weld them firmly together.

19. After the metal block was frozen in the refrigerator, it was taken out for a while and found to be wet. Wipe it with a dry towel, and the metal block is wet again. The reason is ()

A, the water absorbed by the metal block in the refrigerator continues to permeate outward.

B, the water vapor in the air liquefies into water and adheres to the surface of the metal block.

C water in the air adheres to the surface of the metal block.

D, the water in the air is vaporized into water vapor and attached to the surface of the metal block.

20, the following statement, the correct is ()

A. heat the ice, and the temperature of the ice will definitely rise.

B put water at 5℃ into a room at 0℃, and it will freeze.

The "white gas" around the C popsicle is water vapor formed by ice sublimation.

D outdoor water pipes are easy to freeze and crack in winter, because the volume of water becomes larger after freezing.

Fill in the blanks (20 * 1' = 20')

1. In order to make rational use of resources, Xiao Ming put forward the following ideas: making ice by using the electric energy with low electricity consumption at night in summer, and cooling the room by using the heat absorption of ice during the day (fill in the name of material state change); The principle of thermometer is.

There is physics everywhere in life, and you can learn it by careful observation. Do you know that?/You know what? The kitchen also contains a lot of physical knowledge. For example, holding steamed bread that has just come out of the cage and touching some cold water on your hands won't feel very hot. This is because _ _ _ _ _.

3. Please write down the name of the state change to which the following phenomena belong: eating popsicles in summer will give off "white steam" after opening the wrapping paper _ _ _ _ _ _ _; Dry wet hands with a hot air hand dryer _ _ _ _ _; Long-used bulb tungsten filament is thinner than when it was new _ _ _ _?

4. In the summer morning, there are often crystal dewdrops on outdoor flowers and leaves, which is a phenomenon; In the cold winter, when I get up in the morning, I often see a layer of white ice flowers on the window, which is a phenomenon.

5. Put your hands in hot water and cold water at the same time. After a period of time, take out your hands and put them in warm water at the same time. The feeling of hands at this time (choose "same" or "different"). This fact shows that.

6. During the boiling process of water, the temperature of water _ (optional "increase", "decrease" or "unchanged") and process water (optional "endothermic", "exothermic" or "neither endothermic nor exothermic"). At standard atmospheric pressure, the melting point of alcohol is-1 17℃ and the boiling point is 78. The melting point of mercury is -39℃ and the boiling point is 357℃. Do you think _ (choose "alcohol" or "mercury") thermometer should be used to measure the temperature of boiling water? Liquid thermometer uses the characteristics of liquid to measure temperature.

7. The melting points and boiling points of several substances are shown in the table below, so lead is in the state of _ _ _ _ _ _ _ _ _ _ at 300℃, mercury is in the state of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ at 350℃, and alcohol is in the state of _ _ _ _ _ _ _ _ _ at 80℃. It is cold in northern China, so it should be chosen as the temperature measuring liquid.

Material melting point (℃) boiling point (℃)

Clue 328 1740

Mercury 38.8 357

Alcohol-1 1778.5

8. By observing the three schematic diagrams of clothes drying shown in Figure 4, combined with the experience of daily life, we can know that the evaporation speed of liquid is related to the air velocity of liquid, liquid and liquid surface.

Third, the experimental questions

1, wave is crystal, paraffin is amorphous. The melting image of sea waves and paraffin wax collected by Xiaohua through consulting the data is shown in the figure, and the melting image of sea waves is _ _ _ _ _ (fill in the serial number).

The information that can be obtained by analyzing the field is as follows:

①____________________________

②_____________________________

Information that can be obtained by analyzing image b is as follows:

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

2. In order to study the boiling of water, Xiaowen observed the change of water temperature with heating time during heating, and recorded the relevant data in the following table:

Time/Minute 0 1 2 3 4 5 6 7 8 9

Temperature/℃

(1) Please draw points in Figure 12 according to the recorded data, and then use a smooth.

The curve shows the image of water boiling.

(2) According to the image, the heating process of water has the following characteristics:

(Write only 3 points)

① ;

② ;

③ .

3. From June 10 to June 16, 2003, China successfully launched and recovered Shenzhou 5's manned spacecraft.

(1) When the rocket was launched, the high-temperature flame sprayed downward, and a large amount of "white gas" gushed out from the large pool at the bottom of the launch pad. How are these "white gases" formed?

(2) When the return capsule passes through the atmosphere, it rubs with air to generate heat, and the surface of the return capsule is very hot. However, due to the very thick special coating on the surface of the return capsule, the temperature in the capsule remained normal, so some physical changes occurred. Please explain the working principle of volatile coatings.

Liu Juan often helps her mother do housework in her spare time. She killed mosquitoes in her room once, using aerosol insecticide, as shown in the picture. Liu Juan sprayed it with this insecticide-after a while, her hands obviously felt that the metal can with the insecticide was getting cold. She shook the metal can and obviously felt the liquid in it. She learned from reading the instructions that this pesticide is made of a highly volatile chemical raw material and medicine. Please use your physical knowledge to explain why the metal can is cold.