On the question of evaporation, the factors that affect evaporation

Look at your pitiful look, uncle, this Monday, bored to come up with a way for you, use a microwave oven and a balance to do this experiment, first boil the water with a kettle Of course, it is 100 degrees. Then pour 250ml of milk into a cup and put it in the microwave for 5 minutes, then pour the boiling water into the beaker (it is best to put 2 small porcelain pieces in the beaker) 1000ml can be directly said to be 1kg of water, directly put the beaker in the microwave and bake for 20 minutes, then take it out and put it on the balance to weigh the mass m, minus 1kg and the rest is the amount of water that evaporates m. The next thing to do is to look at the microwave oven manual, what is the power p.

Then you can do it a few more times, and the longer you burn it, the closer it is to the actual value", and the average value p*t=heat of evaporation *m (SI units) can be calculated as 42000j kg. I guess no one is going to be more boring than me.

If you need accurate results, and it takes a bit of effort, consider using a highly absorbent substance, measuring its previous mass, and then testing the post-absorbent mass if the substance's water absorption is a physical change.

Let's have a beaker with a more accurate scale.

I think it's better to make a pot with a pot in the middle, like an umbrella on top, catch the steam that comes down first, solidify into water, and return to the other basin below, a bit like an atmospheric circulation.

Temperature, surface area, and velocity of air flow above the liquid surface are the main factors affecting evaporation. Evaporation and boiling are both vaporization phenomena and are two different ways of vaporization. Evaporation is the process of vaporization that occurs on the surface of a liquid.

The main causes of celery that affect evaporation are as follows:

1. Temperature, the higher the temperature, the faster the molecular movement, the faster the evaporation rate, and vice versa;

2. Airflow speed, the stronger the airflow, the faster the evaporation, and vice versa;

3. The larger the surface area of the evaporated object, the faster it is, and the smaller it is, the slower!

Main Factors:

1. Temperature. The higher the temperature, the faster the evaporation. At any temperature, the molecules are constantly moving, and there are always some molecules in the liquid with higher velocity that can fly out of the liquid surface and become vapor molecules, so the liquid can evaporate at any temperature.

As the temperature of the liquid increases, the average kinetic energy of the molecules increases, and the velocity increases, and the number of molecules flying out of the liquid surface increases, so the higher the temperature of the liquid, the faster the evaporation.

2. The size of the surface area of the liquid surface.

If the surface area of the liquid increases, the number of molecules near the surface of the liquid increases, so the number of molecules flying out of the surface increases at the same time, so the larger the surface area, the faster the evaporation.

3. The dissimilar velocity of the air flow above the surface of the liquid.

When a vapor molecule flying into the air collides with an air molecule or other vapor molecule, it may be bumped back into the liquid. If the air above the liquid level moves fast and is well ventilated, the less chance that the molecules will return to the liquid, the faster the evaporation.

There are many factors that affect evaporation, such as temperature, the higher the temperature, the faster the molecular movement, the faster the evaporation, and vice versa; The speed of the airflow, the stronger the monthly strength of the airflow, the faster the evaporation, and the slower the vice versa; The surface area of the object to be evaporated, the larger the faster, the smaller the slower, etc. There are many factors that affect evaporation, such as temperature, the higher the temperature, the faster the molecular movement, the faster the evaporation, and vice versa; The speed of the air flow, the stronger the air flow, the faster the evaporation, and vice versa; The larger the surface area of the body to be evaporated, the faster the liquid, the smaller the slower, etc.

Categories: Science & Engineering.

Problem description: Isn't the boiling point of water 100 degrees? So why does the stagnant water on the ground evaporate? It shouldn't have reached 100 degrees.

Analysis: When you say that the water on the ground evaporates, that is not boiling.

Evaporation can be achieved under certain external conditions, and it does not have to hit 100 degrees.

Boiling: It is the temperature of the water that reaches its own boiling point, and the thermal movement of the water itself intensifies. The heat energy of the water molecules on the surface is greater than the molecular force between the water molecules, and the escape cavity becomes the evaporated water vapor.

Evaporation: also known as volatilization, refers to the action of external forces when water does not reach its own boiling point, such as: the air flow on the surface of water makes water molecules escape and escape. So even if the boiling point is not reached, it can be evaporated.

There are several main factors that affect evaporation:

1. Temperature, the higher the temperature, the faster the movement of the ear, the faster the evaporation rate, and vice versa;

2. The speed of the airflow, the stronger the airflow, the faster the evaporation, and the slower the vice versa;

3. The larger the surface area of the evaporated object, the faster it is, and the smaller it is, the slower!

If it helps, please give a good review or.

I wish you progress in your new semester of Jingbu learning!

The five factors that affect evaporation are light, air temperature, wind speed, humidity, and water surface area, and each of these factors has a different impact on evaporation, which is mainly divided into two categories:

Proportional: light, temperature, wind speed, water surface area (the larger, the more evaporation);

Inversely proportional: humidity (the higher the evaporation, the weaker the evaporation).

In meteorology, it is necessary to take into account the actual situation of evaporation in nature, so there are four main factors affecting the evaporation rate: water source, heat source, saturation difference, wind speed and turbulent diffusion intensity.

1.Headwaters. There can be no evaporation without water sources, so the basic conditions for evaporation are the opening of open water jujube areas, snow surfaces, ice surfaces, or moist soils and vegetation. In the desert, there is almost no evaporation.

2.The evaporation of the heat source must consume heat, and if there is no heat supply during the evaporation process, the evaporation surface will gradually cool, so that the water vapor pressure on the evaporation surface will decrease, so that the evaporation will slow down or gradually stop. Therefore, the rate of evaporation is largely determined by the heat supply.

In fact, the evaporation rate of a stool is often directly expressed by the amount of evaporation heat consumed.

3.The rate of evaporation of the saturation difference is directly proportional to the saturation difference. The greater the saturation difference, the faster the evaporation rate.

4.Wind speed and turbulent diffusion: The vertical and horizontal diffusion of water vapor in the atmosphere can accelerate the evaporation rate. When there is no wind, the water vapor on the evaporation surface is diffused by molecules alone, and the water vapor pressure decreases slowly, and the saturation difference is small, so the evaporation is slow.

When there is wind, the turbulence intensifies, and the water vapor on the evaporation surface is rapidly dispersed to the vast space with the wind and turbulence, and the water vapor pressure on the evaporation surface decreases, the saturation difference increases, and the evaporation accelerates. In addition to the above-mentioned basic factors, evaporation on the continent should also take into account the structure of the soil, moisture, the characteristics of vegetation, etc. Evaporation on the ocean should also take into account the salinity in the water.

Among the factors that affect evaporation, the temperature of the evaporation surface is usually the decisive factor. Since the temperature of the evaporation surface (land and water) varies from year to year and from day to day, the evaporation rate also varies from year to year.