Phase-Changes-in-Matter.pdf

PHYSICAL CHANGES AND PARTICLE MOTION  PHASE CHANGES IN MATTER Phase changes in matter is the process by which matter changes from one physical state or phase to another. The three most common phases of matter are solid, liquid, and gas. For example, from s...

PHYSICAL CHANGES AND PARTICLE MOTION  PHASE CHANGES IN MATTER Phase changes in matter is the process by which matter changes from one physical state or phase to another. The three most common phases of matter are solid, liquid, and gas. For example, from solid to liquid Another example, from liquid to gas  deposition freezing condensation melting evaporation sublimation LET'S TALK ABOUT LATENT HEAT Latent heat is the amount of heat energy that is absorbed or released by a substance during a phase change, such as when a solid melts into a liquid or a liquid vaporizes into a gas. For example, from solid to liquid Another example, from liquid to gas  The heat energy is When ice is heated up, it hea a t actually being used to t h e does not change break the bonds temperature between the molecules immediately, it remains of the ice. You can think at the same temperature of these bonds as tiny until all of it has melted invisible strings that hold a t hea into water. h e t the molecules of the ice together. So, when we add heat to the ice, the ice absorbs the heat, which allows the molecules of the ice to move around more freely and become less tightly packed.  When water is cooled As the temperature down, the opposite hea t t h e a continues to decrease, happens. The heat the molecules start to energy that was become more tightly absorbed when the packed, and they begin water was heated is now to form new released, causing the a t hea intermolecular bonds molecules to slow down h e t between each other. and move less. As a result, the water molecules become less free to move around and vibrate, and they eventually form a rigid structure that we call ice. PHASE CHANGES THROUGH HEATING  PHASE CHANGE : MELTING Melting is a process in which a solid substance changes into a liquid state due to an increase in temperature. When a solid is heated, the kinetic energy of its molecules increases, causing the Melting process of popsicles molecules to vibrate and move more rapidly. Once these bonds are broken, the molecules become less tightly packed, and they are able to move around more freely, which causes the solid to turn into a liquid.  PHASE CHANGE : BOILING Boiling is a process in which a liquid substance changes into a gas state due to an increase in temperature and pressure. When a liquid substance is heated, the energy that is added to it causes the Boiling process of dry ice molecules to move around more rapidly and collide with each other more frequently. As the temperature and pressure increase, this process continues until all of the liquid has been converted into gas. PHASE CHANGE : EVAPORATION Evaporation is a process in which a liquid substance changes into a gas state at a temperature below its boiling point, due to the energy supplied to the surface molecules of the liquid. Evaporation process of water When a liquid is exposed to air, the more energetic molecules near the surface of the liquid can escape into the air as gas molecules. This process continues until all of the liquid has been converted into gas PHASE CHANGE : SUBLIMATION Sublimation is a process in which a solid substance changes directly into a gas state without first becoming a liquid. Sublimation occurs when the temperature Sublimation process of dry ice and pressure are such that the solid can't undergo melting and instead goes directly into the gas phase. This can occur either through the addition of heat, or the reduction of pressure, or both. PHASE CHANGES THROUGH COOLING  PHASE CHANGE : FREEZING Freezing is a phase change in which a liquid substance changes into a solid state. This occurs when the temperature of a liquid is lowered below its freezing point, at which point the molecules become strong enough Freezing process of ice cubes to hold them in a fixed position relative to each other. The freezing point of a substance depends on factors such as pressure and the presence of impurities. PHASE CHANGE : CONDENSATION Condensation is a phase change in which a gas substance changes into a liquid state. This occurs when the temperature of a gas is lowered below its dew point, at which point the molecules become strong enough to Condensation process of water cause them to come closer together and form a liquid. Condensation is a common occurrence in nature and can be seen in different phenomena.  PHASE CHANGE : DEPOSITION Deposition is a phase change in which a gas substance changes into a solid state without first passing through the liquid state. This occurs when the temperature of a gas is lowered below its sublimation point, at which Deposition process of a snowflake point the molecules become strong enough to cause them to come closer together and form a solid. This can result in the formation of frost, snowflakes, or other types of ice crystals.