How to divide physical sublimation and condensation?

Sublimation is the transformation of objects into a gaseous state in a solid state such as sanitary balls, dry ice, artificial rainfall.

Condensation is the turning of an object gas into a solid such as window grilles, etc.

Sublimation is the conversion process from solid to gas, and condensation is the conversion process from gas to solid.

As for the specific cause of transformation, sublimation is affected by heat, because the difference between the gas form and the solid form lies in the density of the molecular arrangement, and the solid is heated to accelerate the molecular movement and transform into gas. Sublimation is also related to the properties of the object itself, we say that camphor can volatilize at room temperature, not because it is not affected by heat, but because its critical temperature for conversion from solid to gas is relatively low.

The influencing factors of condensation are heat and air pressure, which can be condensed by reducing temperature and pressurization.

Why doesn't it need to be liquefied? Because the surrounding environment reaches a critical temperature for the conversion of solids into gases or gases into solids.

Sublimation The process of phase change of a substance directly from a solid state to a gaseous state. Applied disciplines: atmospheric science (first-level discipline); Atmospheric Physics (Secondary Discipline) Definition 2:

A phase transition phenomenon in which a substance changes directly from a solid state to a gaseous state without going through a liquid state. Applied disciplines: electric power (first-level discipline); General Theory (Secondary Discipline).

Condensation is the process of phase transformation of matter from a gaseous state directly to a solid state. Applied disciplines: atmospheric science (first-level discipline); Atmospheric Physics (Secondary Discipline).

Sublimation: The process by which a substance changes from a solid straight lead to a gaseous state.

For example, the phenomenon of sublimation can occur in canon, naphthalene, ice and snow.

For example, the blackening of the inner wall of the incandescent lamp that has been used for a long time is the result of sublimation and condensation;

Another example: in winter, the phenomenon of sublimation occurs when frozen clothes dry out;

Also: the sanitary ball has become smaller, and the clothes are not wet, which is the phenomenon of sublimation;

Condensation: The process by which matter directly changes from a gaseous state to a solid state.

For example, the frost in winter is a phenomenon of condensation and agitation.

Conditions for sublimation and condensation of pure substances.

Pure matter in nature can exist in three aggregate states: solid, liquid, and gas, and under a certain temperature and corresponding pressure, the three aggregate states of solid, liquid, and qi are in the only state of equilibrium coexistence - the three-phase point. It must be noted that only the three-phase point where the solid, liquid, and gas phases of pure matter coexist in equilibrium are discussed. Since helium does not have a three-phase point where solid, liquid, and gas phases coexist in equilibrium, it should be excluded.

The temperature and the corresponding pressure number and chain value of the triple point of different pure substances are different. However, the conditions required for the sublimation and condensation of pure matter are similar. The conditions for the sublimation and condensation of pure matter are:

The temperature and pressure of the vapor of a pure substance must be below the three-phase point temperature and pressure of the substance. If the vapor pressure of a solid pure substance is lower than its three-phase point pressure, the solid substance will be sublimated directly into a gaseous state when the temperature rises. Conversely, if the pressure of a gaseous pure substance is lower than its three-phase point pressure.

When the temperature is lowered below its three-phase point temperature, the gaseous substance will condense directly into a solid state. ,3,The conditions for sublimation and condensation are the same, that is, the boiling point of the object itself is lower than the melting point. ,0,

Physics] [Liquefaction, Sublimation and Condensation] - Understanding Sublimation and Condensation.

Sublimation: It refers to the direct transformation of matter from a solid state to a gaseous state, which is called sublimationIt is an endothermic process, which is characterized by the fact that it directly becomes gaseous without going through the process of melting.

For example, mothballs used in daily life, packed in small bags and placed in a clothing cabinet with wool and the like, will slowly become smaller, from solid to gaseous to fill the entire space, playing the role of killing insects. There are also substances that are easy to sublimate: iodine, ice, dry ice, tungsten, etc.

Practical examples from life: frozen clothes dry in winter; filament thinning; Solid iodine is heated directly into iodine vapor; The dry ice is gone, etc.

Deposition: The direct change of matter from a gaseous state to a solid state is called depositionIt is an endothermic process characterized by the fact that it is directly turned into a solid state without liquefaction.

Practical examples from life: frost;Snow; tree hanging (rime); Grilles; Iodine vapor directly turns into a solid state when cold, etc.

3. The difference between coagulation and solidification: coagulation is the change of a substance from a liquid state to a solid state, which is called coagulation; The condensation is the direct transformation of the substance from the gaseous state to the solid state, which is an endothermic process, which is easy to confuse, how to distinguish it? Although both of them have become solids, there is a difference in the solid states formed.

The solids formed by condensation are characterized by softness, such as: frost; Snowflakes; Rime; Ice flowers on glass windows, etc.

The solids formed by coagulation are characterized by being relatively hard, such as popsicles, but the frost on the paper containing the popsicles is formed by condensation.

Of course, some of them are more complicated, like snow, rime, and in fact, both.

Middle School Physics examines definitions and real-life examples.

Sublimation refers to the phase transformation process of a substance from a solid state to a gaseous state without going through the liquid silver pat state. Sublimation is the process of endothermy, and the enthalpy absorbed by sublimation is called sublimation enthalpy or sublimation heat. The heat of sublimation of the same substance is always greater than the value of the heat of evaporation.

Examples of life are: solid iodine is directly turned into iodine vapor when heated; Mothballs gradually become smaller; Ice is directly turned into water vapor when heated; Dry ice is heated to gaseous carbon dioxide (e.g. white fog on a stage), etc.

Condensation refers to the phenomenon that a substance skips the liquid state and changes directly from a gaseous state to a solid state. It is a change in the state of matter that occurs when the temperature and air pressure are below the three-phase point. The condensation process material is exothermic.

Examples in life include: a light bulb that has been used for a long time will turn from transparent to black; On winter nights, the water vapor in the room often condenses into ice crystals on the window pane, and the "rime" on the branches and the popsicles taken out of the refrigerator form a layer of "frost"; When iodine vapor is cold, iodine particles will appear on the inner wall of the flask; White edges that appear on the leaves in winter.

Condensation: the process by which matter directly changes from a gaseous state to a solid state; The condensation process releases heat.

Common sublimation phenomena: frost; tree hanging (rime); Grilles; Iodine vapor directly turns into solid iodine when it is cold, and so on.

Sublimation: the process by which a substance changes directly from a solid state to a gaseous state; The sublimation process requires endothermy.

Common sublimation phenomena: Frozen clothes dry in winter; The tungsten filament of incandescent lamps becomes thinner; The mothballs (sanitary balls) become smaller or disappear; The dry ice is gone; The snow in the back sun is gone; Solid iodine is heated directly into iodine vapor and so on.

1. Sublimation: The direct conversion of matter from the solid state to the gaseous state is called sublimation.

Causes: In physics, sublimation refers to the phase transition process of a substance from a solid state to a gaseous state without going through a liquid state due to a large temperature difference.

Examples of the actual phenomena of sublimation: iodine becomes iodine vapor, ice becomes water vapor, mothballs disappear.

2. Condensation: the phenomenon that a substance skips the liquid state and changes directly from the gaseous state to the solid state. It is a change in the state of matter that occurs when the temperature and air pressure of a substance are below the three-phase point. The condensation process material is exothermic.

Causes: The conditions for the formation of condensation are relatively special, generally requiring the concentration of gas to reach a certain requirement, and the temperature should be lower than the temperature of the condensation point, such as water vapor when it is below 0 degrees Celsius, etc., and the cause of formation is generally caused by rapid cooling or sublimation.

For example, the actual phenomenon of condensation is that the light bulb will turn from transparent to black after a long time, which is heated when the light bulb is working, and the tungsten vapor formed by the heating and sublimation of the tungsten filament is condensed on the wall of the light bulb into a very thin layer of solid tungsten.

Answer]: A Step 1: Determine the logical relationship between the words in the question stem.

Sublimation refers to the phenomenon that a substance changes directly from a solid state to a gaseous state without going through a liquid state, and condensation refers to the phenomenon that a substance directly changes from a gaseous state to a solid state without going through a liquid state, both of which are physical reactions, and in addition to sublimation and condensation, there are liquefaction, evaporation, etc., that is, the first two words are opposed, and the first two words and the third word are species relations.

Step 2: Determine the logical relationship between the options and words.

Item a: Black and white are both colors, and the colors are red and blue in addition to black and white, that is, the first two words are opposed, and the first two words and the third word are species, which are consistent with the logical relationship of the question stem, and are elected;

Item B: Male, Liang Qian or Female Oak Wu are all genders, but genders are only divided into male and female, that is, the first two words are contradictory, which are inconsistent with the logical relationship of the question stem and are excluded;

Item C: Fractions and decimal numbers are not integers, which are inconsistent with the logical relationship of the question stem, and regret is excluded;

Item D: Animals can be divided into vertebrates and invertebrates according to whether they have or without vertebrates, that is, the first two words are contradictory, which is inconsistent with the logical relationship of the subject stem and is excluded.

Therefore, the correct answer is a.