How is temperature related to the motions of molecules
The Correct Answer and Explanation is:
Temperature is directly related to the kinetic energy of molecules, meaning it measures how fast the molecules in a substance are moving. When the temperature of a substance increases, the molecules gain more energy and move faster. Conversely, when the temperature decreases, the molecules lose energy and move more slowly.
This relationship is explained by the kinetic molecular theory, which states that the particles (atoms, molecules, or ions) of a substance are in constant motion. The faster they move, the higher the temperature. The motion can include vibrations, rotations, and translations (movement from one place to another), and these motions are more pronounced at higher temperatures.
At absolute zero (0 Kelvin or -273.15°C), the motion of molecules theoretically comes to a stop because the molecules have no kinetic energy. This is an idealized condition, and in practice, absolute zero cannot be reached.
In a gas, the temperature is a direct indicator of the average kinetic energy of the gas molecules. If the gas molecules are moving rapidly, they collide more frequently with each other and with the walls of their container, which increases the pressure. In liquids and solids, molecules still move, but their movement is restricted. In solids, particles mostly vibrate in place, while in liquids, the particles have enough energy to move past each other, allowing for fluidity.
Temperature is therefore a measure of the energy within the system, reflecting the average speed of the molecules. As temperature rises, molecular motion intensifies, leading to changes in the state of matter, like melting or boiling. The relationship between temperature and molecular motion is crucial in explaining phenomena such as expansion of materials, changes in state, and even chemical reactions.
