The energy possessed by the irregular movement of a large number of molecules inside an object is called molecular kinetic energy.
Factors affecting the kinetic energy of molecules
Announce
edit
microcosmicThe main factors affecting molecular kinetic energy are the number and type of molecules inside the object,Movement speed；Respectively inmacroscopicThe mass, type and temperature of the corresponding object.According to the formula
=
(n is the number of molecules; m is the single molecular weight;
When the number of molecules of an object increases, the total kinetic energy will increase, which is reflected in the increase of the mass of the material on the macro level;Similarly, when the mass of a single molecule changes, the kinetic energy of the molecule will also change and be proportional to it, which is reflected in the change of material types in the macro perspective;When the average molecular motion speed changes, the molecular kinetic energy changes in square times, and the macro temperature will change accordingly.
Note that it cannot be said that changes in the macro level lead to changes in molecular kinetic energy, but that changes in the micro level molecular properties or motion speed lead to changes in molecular kinetic energy andmacroscopicA change in the nature of an object.
Difference between molecular kinetic energy and kinetic energy
In objectsMolecular thermal motionOfrateDifferent sizes, so eachMolecular kinetic energyThere are also large and small, and constantly changing.stayThermal phenomenonIn our research, we are concerned about the overall expression of a large number of molecules that make up the systemheatTherefore, what matters is not the kinetic energy of a molecule in the system, but the average kinetic energy of all molecules.This average value is called the average kinetic energy of molecular thermal motion.
The temperature of a substance is a sign of the average kinetic energy of its molecular thermal motion.
For different molecules, even at the same temperature, the average kinetic energy is not necessarily the same, but also related to the degree of freedom of the molecule.
