When water is boiling, why does the spout always steam?

Actually, you can feel it, but this feeling is not seeing. Because transparent gases are invisible.

There should be two situations that are most common in everyday life. One is water vapor produced by water boiling. One is the water vapor produced by the evaporation of water at room temperature.

At the spout of the kettle.

In the nearest place, there is no white vapor, where the temperature is very high, and the temperature is higher than the white vapor you see. This is the water vapor produced by the boiling of water.

Not all water vapor is hot. In fact, there is always water vapor in the air. The actual water vapor pressure in the air is relative to the saturation pressure at that temperature.

It's what we usually call humidity. When we feel moisture, it means that the air has a high level of water vapor; When we feel dry, it means that the air has a low level of water vapor. This is the water vapor produced by the evaporation of water.

When water is boiled, the water reaches the boiling point and vaporizes, and the water will turn into water vapor, that is, a gas state, forming bubbles to float.

As for the kettle ringing, it's because of the design. A whistle-like thing was added to the pot because the water vapor was constantly produced and spilled from the inside, like a person blowing into a whistle. In this way, the water can be boiled to alert people, so as to avoid the danger of constantly heating and drying.

Macroscopically, the water boils violently, and the friction with the air vibrates to produce sound; Microscopically: When the molecules boil, they accelerate their vigorous movements, and the high-speed vibrations produce sound.

In the process of boiling water, a phase change occurs, and the temperature is higher than the boiling point of water, so the transformation of water to the gaseous state is much faster than the condensation of water vapor, and the overflow of a large amount of water vapor rubs violently against the relatively still air above the kettle, making a sound.

Microscopically, water molecules.

When the hydrogen bonds between each other break on the surface of the water or where the bubbles are generated, the distance between the molecules increases, and the water molecules that lose the hydrogen bond constraint move violently and vibrate at high speed, and when a large number of water molecules that are free from the hydrogen bond are vibrated together, the sound can be heard by humans.

If you look closely, you will find that the bubbles on the top are small and the bubbles below are large before boiling. The sound is low. When boiling, the bubbles on the top are large and the bubbles on the bottom are small. Loud.

This is because the overall temperature of the water before boiling does not reach the boiling point, due to the uneven heating, the temperature of the lower part of the water body is generally higher than that of the upper part, and the spacing between the water molecules below is greater than that of the top, so that the bubbles can be produced more easily, and because the water temperature above does not reach the boiling point, it will absorb the heat of the gas molecules in the bubbles and liquefy them, and the bubbles are getting smaller and smaller due to the decrease of water pressure, so the overflowing water vapor is less than after boiling, and the vibration of the water molecules in the bubbles is also smaller, so the sound before boiling is smaller. On the contrary, after the water boils, except for the more bubbles and the more intense vibration of the water molecules in the bubbles, the rest of the water body can be regarded as under the same temperature, the total water molecule spacing of the water body is relatively large, and the overflowed water vapor is more intense and the friction with the air is more intense, so the sound produced is greater.

After the water is boiled, the spout of the pot will always be steaming, and the main reason is that after the water is boiled, it reaches the boiling point of the water, so the water will become steam and evaporate.

The temperature of the water after boiling is very high, there is such a heat, so hot water will of course emit hot gas, the spout is the only outlet of the kettle, and the hot air will only come out of the spout.

This is because when the water temperature reaches a certain level, evaporation occurs.

The white gas coming out of the spout when boiling water is small droplets.

Water vapor coming out of the spout after the water boils.

When encountering cooler air, it will liquefy and form small water droplets, which are suspended in the air, which is what we see as "white gas". In summer, when the popsicle paper is opened, the air temperature around the popsicle is low, and the water vapor in the air will liquefy when it encounters the cold air around the popsicle to form "white gas", which is essentially small water droplets.

Mechanism of formation. Liquefaction is the process by which a substance changes from a gaseous state to a liquid state. Liquefaction is the reverse process of vaporization, where gas molecules attract each other and condense into a liquid. When liquefied, the substance emits heat. at critical temperatures.

The following gases can be liquefied. Liquefaction can be achieved by pressurization or cooling, or by pressurizing and cooling.

Gases with critical temperatures above or close to room temperature, such as ether, chlorine, ammonia, sulfur dioxide.

carbon dioxide and certain hydrocarbons.

It can be liquefied by compression at room temperature. Gases with very low critical temperatures, such as oxygen, nitrogen, hydrogen, helium, etc., must be cooled below their critical temperature and then liquefied by isothermal compression.

What is the "white gas" coming out of the spout when boiling water (b).

aWater vapor. b Small droplets.

c. Hot air. dNone of the above statements are true.

It is important to remember that water vapor is a gas, invisible to the naked eye, and whatever can be seen is certainly not water vapor. When boiling water, the temperature is high, water vapor is generated, and after volatilization, it encounters low temperature air and condenses into fine water droplets, which is the "white gas" we see, so "white gas" is also liquid water, but the water droplets are small and look like gas. In the same way, when the weather is cold in winter, the white breath exhaled from our mouth is also the condensed water vapor in our body.

Water vapor is easy to be mischosen, but water vapor is invisible, and white gas should be small water droplets that water vapor liquefies when cold. Pick B,

When water is boiled, it will bubble up, and the gas here refers to water vapor. When water reaches its boiling point, it becomes water vapor, which is what people see as bubbling.

Water vapor, or water vapor for short, is the gaseous form of water (H2O). When water reaches its boiling point, it turns into water vapor. At one standard atmosphere at sea level, the boiling point of water is or 212°F.

Water can also slowly evaporate into water vapor when it is below the boiling point. In a very low pressure environment (less than atmospheric pressure), ice will directly sublimate into water vapor. Water vapor may contribute to the greenhouse effect and is a type of greenhouse gas.

Water is normally liquid and turns into gas once heated. And it's water vapor, which is what you call bubbling.

The physical explanation is that under normal conditions, the spacing between molecules in water is relatively small, and the interaction force is also large. Once heated, the distance between the molecules in the case of an external heat source will also increase, and finally vaporize, and it is the bubbling gas as you say.

Because when the water is boiling, the water is boiling

Definition: The phenomenon in which a liquid is heated beyond its saturation temperature and violently vaporized both inside and on the surface of the liquid.

Therefore, after vaporization, the water condenses in the air and turns into liquid water, so you see white gas.

Boiling water, steaming, is a physical reaction. The boiling point of water is 100 degrees Celsius, and at this time, the form of its existence will change, as you said, when the water is boiled, it will be hot.

When the water reaches its boiling point, the water becomes water vapor, which is seen as the phenomenon of bubbling.

When water is boiled, liquid water becomes water in a gaseous state, and then water in a gaseous state goes to the air and condenses into liquid water, which is what you see as bubbling.

When water reaches its boiling point, it turns into water vapor (is that simple?). ）

When water reaches its boiling point, it turns into water vapor.

1) When boiling water, "white gas" comes out of the spout, which is the water vapor with a high temperature coming out of the spout.

When encountering small water droplets condensed by the cooler air around the spout, it is a liquefaction phenomenon; (2) When the water is boiling, it continuously absorbs heat and the temperature remains unchanged; (3) In the hot summer, people will feel cool when blowing the fan, because the flow of air accelerates the evaporation of sweat, evaporation and heat absorption, but the temperature of the air does not decrease; (4) In the cold winter, the frozen clothes hanging outdoors will also become dry, and the ice will directly change from solid to gaseous, which is a sublimation phenomenon, so the answer is: liquefaction; No change; No change; Sublimation

The cause of white gas is the formation of small water droplets due to the liquefaction of water vapor when it is cold.

But in fact, whether it is boiling water or the formation of car exhaust in winter, there is a distance from the spout. This is because when heating, the metal body has the function of conducting heat, and the air around the spout and the spout are hot and almost at the same temperature as the water vapor, so the water vapor is not cold in this range, and it will not liquefy into small water droplets, and there will be no white gas. In a slightly farther place, the air is cold, and there is a large temperature difference between the high temperature water vapor, so the water vapor will form small water droplets when it is cold.

Because, in winter, the ambient temperature is low, so the phenomenon is obvious. It's like the exhaust gas in winter, and when you breathe in winter, it doesn't form white gas in your mouth.

Water vapour. It is a state of water. When the temperature of water exceeds 100 degrees Celsius (or above the boiling point), the water molecules absorb enough internal energy to convert it into a repulsive force free from the constraints of the molecules, and the distance between the molecules begins to increase, and the water changes from a yard wide liquid state to gaseous water.

This kind of gaseous water does not contain any other substances, and is theoretically distilled water (the air contains impurities) also known as water vapor.

When water is below the boiling point, water can also slowly evaporate into water vapor.

Scientifically speaking, water at room temperature will slowly turn into water vapor and fly into the air, this phenomenon is called.

Evaporate. "He then adds: "Water vapor is a gaseous state of water, which is colorless

The water on the earth became water vapor, and these water vapors formed white clouds in the sky; If the water vapor condenses into larger water droplets, the water droplets will fall down to form rain.

When a large amount of water vapor condenses in the air, it often presents a mass of "white gas", and "white gas" is often mistaken for water vapor.

It is enough to cool the water vapor that boils water into in the air.

By comparing the color, morphology, and form of "white gas" and water vapor

Depending on the location of the gas, it can be seen that the "white gas" is not water vapor, but small water droplets condensed by water vapor floating in the air.

Water vapor is invisible.

White gas is a mist formed by the liquefaction of lead beams when water vapor meets cold air.

It is composed of countless small droplets of water that are subtle and sleepy.

Water vapor is cold at the mouth of the pot to form a small droplet of liquid suspended in the air, this kind of white gas Many people think that the code is water vapor, but in fact, it is not the case, water vapor is invisible, it is a kind of gas posture disturbance.

It's fog. Fog is the condensation of water vapor in the air when it is cold, and it is liquid in small droplets.

Smoke is the extremely fine chain of dust particles formed when an item is burned, and it is in solid form.