What is Change of State? Change of State A change of state is when matter changes its physical form, such as when a solid melts to form a liquid, or when a liquid is heated to form a gas. Changes of state are physical, not chemical, changes. The matter itself does not change its chemical composition. solid liquid gas liquid Physical States & Th ermal Energy The physical state of matter is related to the thermal energy of the particles and the amount of movement of the particles. Matter that is solid has the least amount of thermal energy and the particles have very little movement. Liquids have more thermal energy and the particles exhibit more movement. Gases contain the most thermal energy and the particles are in constant motion. solid least most thermal energy liquid gas Changes of state occur when matter gains or loses thermal energy. For example, a liquid can gain thermal energy when it is heated. The particles move faster, and the liquid matter changes to a gas. If a liquid is cooled, it loses energy and the particles slow down. The liquid then changes to a solid. Changes that occur when energy is added to matter are called endothermic , and changes that occur when energy is removed or lost are called exothermic . exothermic endothermic energy added energy lost © Copyright NewPath Learning. All Rights Reserved. 94-4828 Visit www.newpathlearning.com for Online Learning Resources.
CAUSE Solid Liquid EFFECT Liquid Gas Liquid Solid E Matter can change from one state to another. Write the cause and effect for each example of matter changing states. Copyright © NewPath Learning. All rights reserved. Change in Matter What is Change of State? Pause and Review Matter can change from one state to another. Write the cause and effect of each example of matter changing states. © Copyright NewPath Learning. All Rights Reserved. 94-4828 Visit www.newpathlearning.com for Online Learning Resources.