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Magnetism, Physical State (Solid, Liquid, and Gas), Relative Density

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Magnetism, Physical State (Solid, Liquid, and Gas), Relative Density I know matter has measurable physical properties and those properties determine how matter is classified, changed, and used. I can classify matter based on physical properties, including mass, magnetism, physical state (solid, liquid, and gas), relative density (sinking and floating), solubility in water, and the ability to conduct or insulate thermal energy or electric energy. (5.5A) 5.5AB 4.5AB 3.5ABC What is Matter? • Everything in the universe that has MASS and takes up space (has volume) is classified as MATTER. Vocabulary Preview • Matter • Density • Physical Properties • Sinking • Mass • Floating • Magnetism • Conduct • Physical State • Insulate – Solid – Liquid • Thermal energy – Gas • Electric energy • Volume • Mixtures • Temperature • Maintain • Heating • Iron Filings • Cooling • Solution • Boiling point • Freezing point • Solubility • Dissolve What is Matter? • All matter is made up of small particles called molecules. • These molecules are so small that they can be seen only with the strongest microscopes. • The arrangement of molecules and the amount of energy in the molecules give matter properties (characteristics/qualities). Physical Properties • The physical properties of matter are measurable. • Physical properties are features you can observe with your senses. • Physical properties are characteristics you can measure with a tool. • Physical properties are qualities that can be changed without changing the matter itself. What are the physical properties of matter? 1. Mass 2. Volume 3. Temperature 4. Magnetism 5. Physical State (solid, liquid, gas) 6. Relative Density 7. Solubility in Water 8. Ability to Conduct thermal energy or electric energy 9. Ability to Insulate thermal energy or electric energy Mass • Mass is the amount of matter something contains. • Scientists measure the mass of matter instead of the weight of matter. • Mass is measured in metric units. • Mass is measured with a balance. • Mass is not effected by gravity like weight is. The mass of a dog is the same on Earth as it is on the moon. The weight of a dog is greater on Earth than on the moon. Volume • All matter has volume. • Volume is the amount of space something takes up. • Volume is measured in two ways. – 1. use a ruler: length x width x height – 2. use a graduated cylinder (displacement) Density • Items that are not dense will float. • Items that are very dense will sink. • Relative Density is the physical property of matter that compares the amount of matter to the space taken up. • When we talk about density, we are usually referring to “how crowded” the molecules are. • Density can be measured in grams per milliliter ( g/ml ). • Solids are the densest phase of matter. • Gases are the least dense. Magnetism • Magnetism is a type of force, an attraction, that pulls across a distance. • Matter that contains Nickel, Iron, or Cobalt are magnetic. • Steel is made of Iron, so a magnet attracts anything made of steel like paper clips, staples, and food cans. • Not all metals are attracted to a magnet. The metal must contain iron to be magnetic. A magnet does NOT attract aluminum, most coins, glass, plastic, wood, or rubber. • The center of the earth is iron which is why we have magnetic poles and why a compass works. • A magnet is an object that attracts certain metals (mainly iron). • One end of a magnet is called the south pole. The other end is called the north pole. • One end of a magnet repels while the other attracts. • Opposite poles attract. • The same poles repel. Temperature • Temperature measures the physical property of ‘how hot’ or ‘how cold’ material is. • Celsius is the common unit of measurement for temperature C • Thermometers are the scientific tools used to measure temperature. Boiling point is the temperature at which something becomes a gas. Water has a boiling point of 100 ° C. This means that at 100° C, water begins to change from a liquid to a gas. Melting point is the temperature at which something becomes a liquid. Water has a melting point of 0° C. This means that at 0° C, water in the form of ice begins to change from a solid to a liquid. Freezing point is the temperature at which something becomes a solid. Water has a freezing point of 0° C. This means that at 0° C, water begins to change from a liquid to a solid. Conductors of Heat Energy • Materials that DO transfer heat energy from higher temperature to lower temperature areas. Heat energy flow **************************************************************************************************************************************************** • Examples – materials made of metal and glass Conduction means allowing the transfer of heat from a higher temperature area to a lower temperature area. TEKS 5.7A Insulators of Heat Energy • A material that does NOT transfer heat readily Heat energy Insulator ************************************************************************************************************************************* • Examples – materials made of rubber, wood, cloth – materials that have air pockets Insulation means providing a barrier to the flow of energy, in this case, heat. TEKS 5.7A Heat insulation is also called thermal insulation The blanket keeps body heat (heat energy) close to the boy. Heat energy is not transferred into the surrounding air. The house insulation in the walls and attic will slow down the transfer of heat. In cold weather, inside a warm house will be warmer than the outside temperature. In hot weather, inside a cool house will be cooler than the outside temperature. The styrofoam cup slows down heat transfer. A cold drink in the cup will stay colder than the surrounding air. A hot drink in the cup will stay hotter than the surrounding air. TEKS 5.7A Practice your learning Conductors Insulators • Describe conductors. • Describe insulators. • Give an example of a • Give an example of an conductor. insulator. • Describe a practical • Describe a practical use of a heat use of a heat conductor. insulator. TEKS 5.7A The Physical States of Matter Solids • A solid is matter that has a definite shape and takes up a definite amount of space. • The particles in a solid are close together like neat and even stacks of tiny balls. • The particles are vibrating. Liquids • A liquid is matter that takes the shape of its container and takes up a definite amount of space. • When matter is a liquid, its particles slip and slide around each other. • They move from place to place, but they still stay close to each other. • If you pour a liquid from one container than the other, the amount of matter in the liquid stays the same Gases • A gas is matter that has no definite shape and takes up no definite amount of space. • Like liquid particles the particles in gases are not arranged in any pattern. • Unlike liquids, particles in gases don’t stay close together. • This is because the particles in gases are moving much faster than the particles in liquids. How does matter change? Matter • Can be changed from one state to another and back by heating or cooling PHASE CHANGES Description of Term for Phase Heat Movement During Phase Change Change Phase Change Heat goes into Solid to Melting the solid as it liquid melts. Heat leaves the Liquid to Freezing liquid as it solid freezes. PHASE CHANGES Description of Term for Phase Heat Movement During Phase Change Change Phase Change Vaporization, Liquid to which includes Heat goes into the gas boiling and liquid as it vaporizes. evaporation Heat leaves the gas Gas to liquid Condensation as it condenses. Heat goes into the Solid to gas Sublimation solid as it sublimates. What is happening? STARTS CHANGES TO WHAT HAPPENED? Solid Liquid Liquid Gas Liquid Solid Gas Liquid What happens when we mix matter? 5.5 CD 4.5C 5.3D Mixture – a combination of two or more materials that can be separated •Each material (substance) keeps most of its own physical properties. Solution – a transparent or translucent liquid mixture •Solutions are often solids dissolved into liquids. •Solutions can also be liquids dissolved into liquids. •The physical properties of the ingredients change in a solution. Solubility • Solubility is the physical property which describes how easily a substance breaks down smaller and smaller pieces until it gets so small that it dissolves and you can no longer see it. • If something is soluble it means it will dissolve. • A solid dissolves when it mixes evenly with the liquid and disappears. • A liquid dissolves when it mixes evenly with another liquid and disappears. .
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