What is the relationship between phase change and heat energy?
During a phase change, a substance undergoes transition to a higher energy state when heat is added, or to a lower energy state when heat is removed. Heat is added to a substance during melting and vaporization. Latent heat is released by a substance during condensation and freezing.
How is temperature related to changes in the state of matter?
Physical conditions like temperature and pressure affect state of matter. When thermal energy is added to a substance, its temperature increases, which can change its state from solid to liquid (melting), liquid to gas (vaporization), or solid to gas (sublimation).
What is the relationship between energy and molecular motion?
the relationship between molecular motion and kinetic energy is that the faster the molcules are moving, the higher the kinetic energy is. what is the relationship between molecular motion and temperature? The relationship between the two is that the higher the molecular motion is, the higher the temperature is.
What happens when the molecular motion increases?
Heating a substance increases molecular motion. Cooling a substance decreases molecular motion. As molecular motion increases, the space between molecules increases. As molecular motion decreases, the space between molecules decreases.
What is the relationship between temperature and molecular motion?
As the temperature increases, the kinetic energy of the molecules of the liquid increases. The movement of the molecules gradually overcomes forces of attraction between the molecules, with the result that they have greater freedom to move, over greater volumes.
What are the changes in molecular motion and state that take place when temperature decreases?
At low temperatures, molecular motion decreases and substances have less internal energy. Atoms will settle into low energy states relative to one another and move very little, which is characteristic of solid matter.
How does the movement of water molecules change when heat energy is added?
As heat is added to a liquid, the molecules move faster and faster until they break free of the liquid and become a gas. Sample answer: Liquid water molecules move faster and faster until they break free of the liquid. Temperature: 100 °C C. Water is cooled to the freezing point.
How do molecules move in hot and cold water?
Molecules in a gas have lots of energy and spread out even more than molecules in a liquid. Warm water has more energy than cold water, which means that molecules in warm water move faster than molecules in cold water. The food coloring you add to the water is pushed around by the water molecules.
How do molecules move in hot and cold air?
When air gets warmed by a hot burner, it’s molecules speed up and spread out. Then, cold air molecules squeeze the warm spread-out molecules up. That’s why people say hot air rises. It’s natural convection.
Does moving molecules make things cool down or heat up?
The faster-moving atoms or molecules of the hotter substance contact slower-moving atoms or molecules of the cooler substance. An object or substance can’t get colder by adding “coldness” to it. Something can only get colder by having its atoms and molecules transfer their energy to something that is colder.
How do we experience heat?
The human body exchanges heat with the surroundings by four routes: conduction (that is, between objects in contact), convection (to a surrounding liquid or gas), radiation (by the absorption and emission of electromagnetic radiation) and evaporation (the phase change of water from liquid to gas).