Brownian motion of the thermal motion of the molecule, thermal motion of the molecule

It is the irregular motion between molecules, because the speed of molecular motion is related to temperature, the higher the temperature, the more intense the molecular movement, the faster the diffusion, so the irregular motion between molecules is also called thermal motion.

It's the irregular movement of molecules that happens all the time, and the degree of which is proportional to temperature.

First, clarify a few basic knowledge:

1. There are two ways to change the internal energy of an object: 1) heat transfer; 2) Do work.

Specifically: if the object absorbs heat or the outside does work on the object, the internal energy of the object will increase, and the internal energy of the object will decrease if the object releases heat or the work done by the object on the outside.

2. The sum of the kinetic energy and molecular potential energy of all molecules in an object moving irregularly is called the internal energy of the object. From this concept we can know that the internal energy of an object is determined by three factors of the object:

1) the number of molecules in the object; 2) the kinetic energy of the molecule; 3) The potential energy of the molecule.

3. The higher the temperature of the object, the more intense the molecular motion in the object, and the greater the kinetic energy of the molecule (because the kinetic energy of the molecule is determined by the mass of the molecule and the speed of the molecular motion, the mass of the molecule here is constant, so the greater its velocity, the greater its motion); A constant temperature indicates that the intensity of the movement of molecules in an object does not change.

Second, your question for your reference:

1. "When an object absorbs heat, the motion of molecules must be accelerated" is false.

Because: 1) The internal energy of the object may not increase after absorbing heat, for example, the object may do work on the outside world while absorbing heat, and the internal energy may increase, remain unchanged, or even decrease. 2) When the internal energy of the object increases, the kinetic energy of the molecule may not increase, for example, when the crystal is melted, it absorbs heat and the temperature does not change, that is, at this time, the potential energy of the molecule increases, the kinetic energy of the molecule does not increase, and the molecular motion does not accelerate.

2. "The higher the temperature of the object, the more intense the thermal movement" is true.

This is an experimental fact. It is also a theoretical result (physics believes that temperature reflects the average kinetic energy of the molecules in an object).

3. "The acceleration of molecular motion is not necessarily an increase in internal energy" is.

It should be understood here that the temperature of an object increases, its molecular motion accelerates, and its internal energy increases. Reason:

The internal energy of an object is determined by three factors of the object: 1) the number of molecules in the object; 2) the kinetic energy of the molecule; 3) The potential energy of the molecule.

Here, for an object, the "number of molecules in the object" does not change, when the temperature of the object increases (the molecular motion accelerates), its "molecular potential energy" does not change, and when the molecular motion accelerates, the mass of the molecule does not change, the kinetic energy of the molecule increases, and the internal energy of the object increases. (Special note here: prerequisites).

From the fact that "the internal energy of an object is determined by the three factors of the object", we can judge many related issues. For example: "hot water has more internal energy than cold water" is wrong. The main thing is that the "number of molecules" is uncertain.

First of all, the observed phenomenon is the irregular movement of small particles.

Then, will someone ask to think about why these small particles or particles move randomly?

Then, there will definitely be people who will make scientific observations and explanations for this phenomenon.

The final discovery was because:

Deerso first pointed out that Brownian motion is caused by the unbalanced force of particles by the collision of liquid molecules. Subsequently, in 1904, the French scientist H Pancarré further explained that large objects (such as millimeters of linearity) will be hit by moving atoms from all sides, and the blows will be very frequent, and the laws of probability will make them compensate for each other, so they will not move. The tiny particles of the jujube are hit so little that they can't compensate.

That is to say, Brownian motion is a macroscopic manifestation of the irregular thermal motion of liquid molecules without pause. 1905-19

06 a Einstein celery midtan and mvon Smolukhovsky published a theoretical analysis of Brownian motion. In 1908, Piran verified Einstein's theory experimentally, making the physical image of molecular kinetic theory widely accepted. ”

Hello, now I am here to answer the above questions for you. Brownian motion is not a molecule doing irregular motion, Brownian motion is not a hot motion defeat seepage letter demolition boring many friends still don't know, now let's take a look at the bend. <>

Hello, now I am here to answer the above questions for you. Whether Brownian motion is a molecular irregular motion, whether Brownian motion is a hot motion I believe many friends still don't know, now let's take a look!

1. Brownian motion is the phenomenon of suspended particles moving irregularly without stopping.

2. Molecular thermal motion does not belong to Brownian motion because molecules suspend particles.

3. Brownian motion refers to the irregular motion of small particles due to the impact of the irregular thermal motion of molecules under the influence of molecular thermal motion.

Brownian motion is used in the field of chemistry.

Solid particles suspended in a gas or liquid are hit by gas or liquid molecules and act as a never-ending, irregular motion, which is called Brownian motion.

Molecular thermal motion is used in the field of physics.

The molecules are constantly moving in an irregular motion.

Although they are all constantly moving, the former is due to the impact of molecules, and the latter is blind because the charges in the molecules are unevenly attracted to each other and cause movement.

So it's not a nonsense.

Brownian motion refers to the movement of small solid particles in a dispersed system, and molecular thermal motion refers to the irregular motion of all molecules, and the two point to each other. Brownian motion refers to the movement of small particles in a dispersed system under the influence of molecular thermal motion. It is due to the impact of the irregular thermal motion of the molecules, and the irregular motion of small particles.

Brownian motion refers to the never-ending, irregular motion of particles suspended in a liquid or gas. The thermal motion of molecules is that objects are made up of molecules, atoms, and ions (water is made up of molecules, iron is made up of atoms, and salt is made up of ions), and the molecules of all matter are in constant motion, and they are moving irregularly. The higher the temperature, the more intense the Brownian motion; The fewer the particles, the more intense the thermal motion of the molecules.

Brownian motion and molecular thermal motion are not the same thing.

As long as there is a temperature object, the molecules inside it will not be stationary, but will never stop irregular motion, we call the motion of the molecules inside the object itself molecular thermal motion. But the movement itself cannot be seen with the naked eye.

It was found that the pollen particles are put into the liquid, and the pollen particles can be seen from the microscope to do irregular motion, in fact, it is not that the pollen particles themselves have the power to move, but the liquid molecules around it are doing molecular thermal motion, and the thermal movement is irregular, and the speed of each molecule is different, so under the impact of these liquid molecules, the pollen particles are forced to make irregular movements, which we call Brownian motion.

Answer: The essence of Brownian motion is thermal motion.

Brownian motion is a macroscopic manifestation of the irregular thermal motion of liquid molecules without pause.

The analysis is as follows: Since the molecule is never going to do irregular motion. The suspended particles that are impacted by the molecules will be subjected to uneven forces at different times and in different directions, and will also move irregularly. Although the motion of suspended particles is not the movement of molecules, the irregular motion of suspended particles can essentially reflect the characteristics of irregular thermal motion of molecules.