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Matter WHAT DO YOU KNOW ABOUT STATES OF MATTER? • What are the three commonly known states of matter? • What is the gas, liquid and solid form of water? • How does matter change state? Watch this animation on states of matter (click “Play Video”): Animation: States of Matter http://teacher.scholastic.com/activities/studyjams/matter_states/ Scholastic WHAT ARE STATES OF MATTER? States of matter are the physical forms a substance can take. There are three common states of matter: solid, liquid, and gas. Each of these states is also called a phase. THE THREE COMMON STATES OF MATTER Most substances, like water, can exist in all three states. An iceberg is made of water in solid form. This glass contains liquid water. A cloud is made of water vapor, a type of gas. SOLIDS • Solids have a definite shape and volume, or amount of space an object takes up. The particles that make up a solid are packed tightly and held together by strong forces. • Solid particles vibrate in place but cannot move from their position, which is why solids maintain their rigid shape. LIQUIDS • Liquids have a definite volume but not a definite shape. The particles that make up a liquid are spaced farther apart and are held together by weaker forces than solids. • Liquid particles move slightly, which allows liquids to flow and take the shape of the container they are in. GASES • Gases do not have a definite volume or shape. The particles that make up a gas are fastmoving and are held together by extremely weak forces. • Gas particles move freely and will expand to fill a container of any size or shape. CHANGES OF STATE • Matter can change from one state to another. • Even though the physical form of the matter changes, it remains the same substance. • Changes of state occur when thermal energy (heat energy) is absorbed or released by a substance. WHAT ARE THE CHANGES OF STATE? GAS SOLID LIQUID HOW DOES MATTER CHANGE STATE? Temperature Changes of State • • Thermal Energy Added As heat increases, a substance changes from a solid to a liquid, and finally to a gas. As heat decreases, a substance changes from a gas to a liquid, and finally to a solid. DISCUSSION QUESTIONS • How does pressure and temperature affect the state of water, carbon dioxide, and hydrogen? Use this interactive PBS Web site to find out: www.pbs.org/wgbh/nova/zero/matt-flash.html. • On Earth, we typically see gases, liquids, and solids. a fourth state of at this Web site: But is Learn thereabout a fourth state ofmatter matter? http://www.spaceweathercenter.org/amazing_plasmas/02/02.html HANDS-ON SCIENCE (No Lab Required) This demo explores melting points. Materials chocolate chips, candy-coated chocolates, baggies, two mugs, water, thermometer Directions 1. Place chocolate chips and candy-coated chocolate in separate bags. 2. Place each bag of chocolate in a half-filled mug of room-temperature water. 3. Your teacher will continue to increase the temperature in each mug by adding boiling water a little at a time. 4. As a class, monitor the temperature with a thermometer until the chocolate starts to melt in the bag. Conclusion At what temperature does each type of chocolate start to melt? Why do you think this is? Solid: has definite shape and volume Liquid: has definite volume but not shape Gas: does not have definite volume or shape. Physical Change: a change that does not result in new substances. Freezing point: temperature when liquid changes to a solid: water is 32 F or 0 C Melting point: temperature when solid changes to liquid Boiling point: temperature when liquid changes to a gas. Water: 212 F… 100 C Sublimation: changes from a solid to a gas. Example: dry ice Condenses: changes from gas to liquid because it cools down. Example: water on the outside of a can of pop. Matter: has mass and takes up space. Mass: the amount of matter something has Volume: amount of space something takes up Weight: measure of the force of gravity on an object’s mass Density: measurement of how much matter is in an object. Mass divided by volume Physical Properties: color smell freezing point melting point boiling point density solubility Chemical Properties: odor color change: trees in autumn oxidation flammability Ph (acid or base) Physical Change: doesn’t change what the substance is. Can be reversed. Examples: torn piece of paper; mixing sugar and water Chemical Change: causes a chemical reaction and a new substance is formed. Cannot be reversed. Examples: paper burned; baking a cake Law of Conservation of Mass: Matter can never be created or destroyed. All matter is present just changes form. Dmitri Mendeleev: known for putting the periodic table together as we know it today. The Periodic Table of elements organizes the elements based on atomic number. There are approximately 100 elements. They are organized into 18 groups and 7 periods. Atoms Atoms: the smallest parts of something that can be identified. a. Protons: positive charge/found in the nucleus b. Neutrons: neutral charge/found in the nucleus c. Electrons: negative charge/outside the nucleus d. Nucleus: in the center of the atom Atomic Number: represents the number of protons and electrons. Atomic Mass: represents the number of protons and neutrons. If I use Carbon---the atomic number is 6. That means carbon has 6 protons and 6 electrons. To find out how many Neutrons there are plug in the numbers: atomic mass is 12 which equals number of protons and neutrons. If the protons are 6 then the neutrons are 6. protons + neutrons = atomic mass Element: a substance that cannot be split into simpler substances. Made up of only one kind of atom. Examples: H, O, N, Cl Mixture: any substance made of 2 or more atoms that can be separated physically. Examples: Tossed Salad, Chex Mix, Cereal Solution: mixture where particles of different substances are mixed evenly: Example: Powdered fruit drinks Compounds: matter made of 2 or more different elements. Examples: water: H2O & Table sugar: C12H22O11 Molecule: any substance made of 2 or more atoms. Examples: Water:H2O & Table Salt: NaCl & Ozone: O3 Simple Machines Notes over Simple Machines LEVER: 1. Fulcrum: the pivot point where it rotates 2. Effort/Force: a push or pull 3. Resistance/Load: an object being moved. 4. 3 Classes of levers: a. 1st: Fulcrum in the middle: a crow bar, see-saw b. 2nd Load in the middle: wheel barrel, nutcracker c. 3rd Effort in the middle: broom, rake 5. M.A.= effort arm divided by resistance arm Notes over Simple Machines Wheel/Axle: • The bigger the wheel compared to the axle the easier the work. Examples: car wheels, door knobs, skates, bike tires 2. M.A.= Diameter of wheel divided by the diameter of the axle Notes over Simple Machines Pulley: • Fixed pulley: attached to something. No M.A. But changes direction of effort. 2. Moveable pulley: moves with the object. Only half as much effort is needed. 3. Block and Tackle pulley: used to lift heavy objects. 2 pulleys are used. 4. M.A. is multiplied by the number of strands in a pulley. Notes over Simple Machines Screw: An inclined plane wrapped around a pole. Examples: Nut/bolt, jar lid, road around a mountain, Notes over Simple Machines Wedge: An object that cuts separates things. Examples: Knife, door stop, ax, scissors, fork, tip of nail Notes over Simple Machines Inclined plane: A flat sloped surface. Examples: Ramp, roof, staircase Notes over Simple Machines 1. Simple Machines are used to reduce the force needed to move an object while increasing the distance over which the force is applied. 2. Friction will reduce the output of simple machines or increase the amount of force needed. 3. Force needed to move an object can be reduced by combining 2 or more simple machines to create a compound machine. 4. The force required to lift an object by yourself is equal to the weight of the object. BUT when you use a simple machine the object can be lifted with less force. Newton’s Laws of Motion NOTES 1. Newton’s 1st Law: an object at rest stays at rest and an object in motion stays in motion unless a force acts on it. 2. ALSO CALLED THE LAW OF INERTIA FORCES: a. Gravity: pulls/holds onto things b. Friction: wears down, slows down, heats up when 2 objects come in contact with each other. c. Air resistance EXAMPLES: a book on the table, swing NOTES 2. Newton’s 2nd Law: the greater the force the greater the acceleration. The larger the mass of the object the greater the force required to accelerate or slow down the object. EXAMPLES: empty/full grocery cart & Diesel or small car ACCELERATION: speeding up FORCE: the push or pull on an object NEWTONS: (N)the unit of force required to accelerate an object. (1 kg-1 m per s2) NOTES 3. Newton’s 3rd Law: For every action there is an equal but opposite reaction. EXAMPLES: firing a gun, rocket shooting NOTES Balanced forces: when 2 or more forces act on the same object equally in opposite directions. Unbalanced forces: unequal forces that act on an object and change its motion. Motion Graphs Interpret The Graph Below: Interpret The Graph Below: The graph shows an object which is not moving (at rest). The distance stays the same as time goes by because it is not moving. Interpret The Graph Below: Interpret The Graph Below: The graph shows that the objects distance increases as time passes. The object is moving and so it has velocity. The straight line shows it is a constant (not changing). Interpret The Graph Below: Interpret The Graph Below: Just like the previous graph, this graph shows an object moving with constant velocity Interpret The Graph Below: Interpret The Graph Below: The curve in the graph shows that the objects velocity is changing as time passes. This is acceleration. Interpret The Graph Below: Interpret The Graph Below: In the first part of the graph the object is moving with constant velocity. In the second part of the graph the object is at rest (not moving). In the third part the object is again moving with constant velocity. Interpret The Graph Below: Interpret The Graph Below: The graph shows that the objects velocity does not change as time passes. It shows constant velocity. Interpret The Graph Below: Interpret The Graph Below: The graph shows that the objects velocity is increasing as time passes – it is accelerating. The straight line shows that it is constant acceleration. Click here for more review: http://www.usoe.k12.ut.us/curr/sci ence/sciber00/8th/forces/sciber/int ro.htm Heat Temperature: the measure of how hot or cold something is. Thermometer: a device used to measure the temperature of an object. Heat: energy that is based on the temperature and mass of an object. Absolute Zero: the lowest possible temperature. Kelvin: 0 Celcius: -273 Fahrenheit: -459.7 Celcius: temperature scale based on freezing & boiling points of water. Freezing: 0 Boiling: 100 Fahrenheit: a temperature scale based on water freezing. Freezing: 32 Boiling: 212 Kelvin: a temperature scale based on absolute zero. Freezing: 272 Boiling: 373 Conduction: transfers heat energy through direct contact. Conductors: materials that allow heat to pass easily. Examples: water, metals Convection: Transfer of heat energy in a liquid or gas in a circular motion. Examples: oven, heater in house, magma under the surface of the earth. Radiation: transfer of heat energy through the emptiness of space. Examples: sun, microwaves Insulators: material that does not allow heat to pass through easily. Examples: rubber, cloth, styrofoam, wood LIGHT 1. 2. 3. 4. 5. 6. LIGHT VOCABULARY Opaque: does not emit light (ex: cardboard) Luminous: emits light (ex. Sun) Transparent: light is able to pass through the object. (ex: glass) Translucent: some light can pass through (ex: wax paper) Refraction: bending of light waves (ex. Pencil in water) Reflection: bouncing back of light waves (ex. Looking in a mirror) LIGHT VOCABULARY 7. Transmission: some light is absorbed and some passes through the object onto the other side. 8. Absorption: If the object looks white, it is because all or nearly all of the radiation is reflected. If the object appears to have any color other than white, however, it means that all the visible radiation has been absorbed except for the color you see. Objects that absorb all the radiation striking them are known as black bodies. 9. White light reflects light and is made up of 7 colors. 10. The color of an object is determined by the color of light reflected by the object.