The temperature of an object with a certain mass increases, the internal energy increases, why

As the temperature increases, the internal energy increases", a phrase that applies to thermodynamics in the narrow sense. The internal energy of an ideal gas is only a function of temperature, so this statement is true for an ideal gas. This statement is true without considering chemical reactions, nuclear reactions, etc.

But if the system is a chemical reaction, then this is not necessarily true. For example, in a chemical reaction in a closed system: hydrogen + oxygen is burned to produce water, the temperature of the system rises, but the internal energy does not change.

Conversely, the increase in internal energy does not necessarily mean that the temperature will increase. For ideal gases, the internal energy increases and the temperature must increase. But not necessarily otherwise.

Take phase transition, for example: at one atmospheric pressure, the liquid water phase of 100 degrees Celsius changes to water vapor at 100 degrees Celsius, and the temperature does not change, but the internal energy increases. In turn, the water vapor phase of 100 degrees Celsius changes to liquid water at 100 degrees Celsius, and the temperature does not change, but the internal energy decreases.

In the case that the potential energy of the molecule cannot be ignored, this sentence is false, and the answer is not necessarily an increase. At the same time, if the external work of the object expands, and the work done is greater than the kinetic energy of the molecule at the temperature increase, the internal energy decreases.

The temperature has risen to indicate the acceptance of energy, and the internal energy is now explained by the ** of the atom. According to the fundamental theorem of physics, energy does not disappear, and energy is transferred from the outside to the object, which is classified as internal energy.

The rate of movement of the internal molecules accelerates and the kinetic energy increases.

Not necessarily. The magnitude of internal energy is related to the mass, volume, temperature, and type of matter that makes up the object. At this stage, the main focus is on the relationship with temperature. When the temperature of an object increases, its internal energy increases, and when the temperature decreases, its internal energy decreases.

It is wrong to remember that "when the temperature does not change, its internal energy must not change". For example, when the crystal melts and the liquid boils, the temperature remains the same, but it absorbs heat and the internal energy increases. When the temperature does not change, its internal energy may also decrease (think about why?).

Similarly, when an object emits heat, the temperature does not necessarily decrease.

If the relationship between these three is explained in detail, there are six sentences, only one sentence in the middle of the period is correct, and the remaining five sentences are all wrong: if the temperature of the object increases, the internal energy of the object must increase; Because (the mass, Chizhou's state does not change, the higher the temperature, the greater the internal energy), the temperature of the object increases, then the object must absorb heat; Because the temperature of the object rises and the outside world does work on the object. )

If the internal energy of the object increases, the temperature of the object must increase; ✘

Because the internal energy of the object increases, it is possible that the object has undergone a disturbance change in the state of matter, or the mass has changed. If the internal energy of the object increases, the object must have absorbed heat; (The increase in the internal energy of the object may also be due to the work done by the outside world on the object).

If the object absorbs heat, the temperature of the object must increase; (When melting, the temperature of the object does not change) If the object absorbs heat, the internal energy of the object must increase. (When absorbing heat, external work may be done, and internal energy may not necessarily increase.) )

This is a controversial issue. It can be considered correct.

Internal energy is the sum of the kinetic energy and potential energy of the molecule.

Temperature is only related to the kinetic energy of the molecule, and according to the magnitude of the temperature, only the kinetic energy can be compared, and the magnitude of the potential energy cannot be judged.

The Chinese language is very wonderful, and different people have different understandings of the same sentence. For example:

1.Understanding from the relationship between temperature and internal energy, the higher the temperature, the greater the internal energy, which is correct.

2.In the case of gases, the molecular potential energy is negligible. In the case of a solid liquid, the change in molecular potential energy is often caused by a change in temperature (kinetic energy change), and no matter how large the change in molecular potential energy is, it cannot be greater than the cause of it.

Of course, is there really a state where the temperature is higher, the potential energy is smaller, and the internal energy is smaller? Theoretically, it exists, and how to achieve it remains to be achieved.

The microscopic meaning of temperature is that the average kinetic energy of the molecule ek=3kt 2, which is for diatomic molecules, and the average kinetic energy of polyatomic molecules is slightly more complicated by taking into account vibration, rotation, etc. where k is the Boltzmann constant and t is the Kelvin temperature.

The internal energy in the narrow sense refers to the thermal kinetic energy of the molecule, that is, the internal energy that is variable in the general physical process. It is the sum of the kinetic energy and potential energy of the molecule when all the molecules inside the object are doing thermal motion.

According to the above two points, the high temperature, the average kinetic energy of the molecule increases, and the internal energy increases.

The concept of physics is easy to make mistakes, the temperature of the object increases, and the internal energy of the object increases?

Definitely, the internal energy is the kinetic energy of the irregular motion of the molecule and the potential energy of the molecule, and the increase in temperature makes the irregular motion intensify, and the internal energy will increase. Of course, this is the definition of internal energy in middle school, strictly speaking, chemical energy, electromagnetic energy, nuclear energy, etc. in molecules are all part of internal energy.

It must be because of the increase in temperature, the thermal movement of the molecule is violent, the kinetic energy of the molecule increases, and the internal energy increases.

If it is wrong to say this: the temperature of an object increases, its internal energy must increase.

The internal energy includes the self of the thermal motion of the sub-molecules.

Kinetic energy and intermolecular potential energy. The increase in temperature Bai corresponds to an increase in the average kinetic energy of the thermal movement of DU molecules in the system. And the potential DAO energy is still uncertain.

Hence the total internal energy is uncertain. For an ideal gas, the intermolecular potential energy is 0, and the internal energy increases as the temperature increases. There are interactions between molecules, which is more complicated.

Depends on the situation.

When the same substance is at the same temperature in different states.

Molecular potential energy. Generally speaking, the internal energy of the gas is greater than that of the liquid and the internal energy of the solid is greater than that of the solid.

For example, if 0 degrees Celsius ice turns into 0 degrees Celsius water, it needs to absorb heat, indicating that the energy of the latter is higher, and the water becomes water vapor with a boiling point, and when it reaches the boiling point, it continues to be heated, and the water will become water vapor, which is also illustrated.

The internal energy of water vapor should be high.

Because the internal energy is not only determined by temperature, but also by the force between molecules.

If the state of matter is different, the magnitude of the intermolecular force is different, and the internal energy cannot be compared just by temperature.

For example, solid molecules act stronger than liquids, which in turn are stronger than gases

First of all, we need to understand these concepts, and in a broad sense, internal energy is the energy determined by the internal conditions of the system. The thermodynamic system is composed of a large number of molecules and atoms, and the energy stored in the system is the sum of the various energies of all microscopic particles, that is, the sum of the kinetic energy, potential energy, chemical energy, ionization energy, nuclear energy, and so on of the microscopic particles.

Generally speaking, temperature is a measure of how hot or cold an object is with a thermometer.

To sum up: when the temperature of an object rises, it must absorb heat or the outside world does work on it, and the internal energy of the object increases.

If you're satisfied, take it.

The internal energy must increase when the temperature increases, and the only way to change the internal energy is heat transfer and work, which are equivalent.

"When the temperature of an object increases, its internal energy must increase. "It's wrong. Changes in volume are not taken into account.

The first cylinder is insulated, and the piston is slowly pulled outward, and the gas volume increases and the pressure decreases. Internal energy increases.

The outside world has done work on the air in the piston, and the intermolecular potential energy increases;

Due to the adiabatic cylinder, the molecular kinetic energy does not change;

To sum up, the internal energy should of course be increased.

The change in the internal energy of the object e w+q

If the temperature of the object increases, it can only be determined that the object absorbs heat, and the work done cannot be determined, indicating that 1 is wrong.

When the energy inside an object increases, it may be an increase in temperature, heat absorption, or both. Note 2 is false.

The internal energy is absolutely reduced.

You're looking at the gas inside the cylinder, not the cylinder. The external force does work on the cylinder but not on the gas, on the contrary, the gas presses the piston of the cylinder and has a displacement in the direction of the internal air pressure, w=ps (area) s (displacement).

This question is even absolutely certain.

1) Compare the two beakers A and B.

It can be seen that the substances are all water, the same elevated temperature, the same mass is not the same ridge, and the heating time is different, so it can be concluded that the amount of heat absorbed by the same substance with different masses is related to the mass of the object when it is raised to the same temperature

2) Comparing the experimental records of the two beakers C and D, it can be seen that the substance is kerosene.

The mass is equal, the raised temperature is different, and the heating time is not the same, so it can be concluded that the amount of heat absorbed by the same substance with different masses when it is raised at different temperatures is related to the increased temperature

Comparing the experimental records of the two beakers A and C, it can be seen that A is water and C is kerosene, the mass is equal, the raised temperature is the same, and the heating time is different, so it can be concluded that the amount of heat absorbed by different substances with the same mass is related to the type of substance when the same temperature is raised

4) Combined with the above conclusions, when the temperature of an object increases, the amount of heat absorbed is related to the mass of the substance, the temperature of the increase, and the type of substance

Therefore, the answer is: (1) quality; (2) elevated temperatures; (3) type; (4) the quality of the substance; elevated temperatures; The type of substance