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  1. 1. Chapter 2 The Properties of Matter What is matter? Which part of this course is more concerned with matter?
  2. 2. Matter <ul><li>Everything is made of MATTER! </li></ul><ul><li>Matter is anything that has volume and mass. </li></ul><ul><li>Volume is the amount of space an object takes up, or occupies. </li></ul>
  3. 3. Measuring the volume of liquids <ul><li>Liquids have volume. We measure that volume with a graduated cylinder. </li></ul><ul><li>Notice the meniscus in the graduated cylinder. </li></ul><ul><li>Always measure at the bottom of the meniscus! </li></ul><ul><li>A liquid in any container has a meniscus. </li></ul><ul><li>Liters (L) and mL (milliliters) are most often used to express the volume of liquids. </li></ul>
  4. 4. Solid Volume <ul><li>The volume in a solid is always expressed in cubic units. </li></ul><ul><li>Cubic means having “three dimensions.” </li></ul><ul><li>Cubic meters(m 3 ) or cubic centimeters(cm 3 ) are most often used to express the volume of a solid. </li></ul><ul><li>The 3 in m 3 signifies that three quantities were used to get the final result. (That is a derived quantity!) </li></ul><ul><li>If each side in the cube below is 2m, what is the volume of the cube? </li></ul><ul><li> __________ </li></ul>
  5. 5. The Volume of Solids, Liquids, and Gases <ul><li>1 mL = 1 cm 3 REMEMBER THAT! </li></ul><ul><li>That is why you can compare the volume in liquids to solids. </li></ul><ul><li>How do you measure the volume of a gas? </li></ul><ul><li>You can’t see, so how do you measure it? </li></ul><ul><li>ex: balloon </li></ul><ul><li>_________________________ </li></ul>
  6. 6. Matter and Mass <ul><li>What is mass? </li></ul><ul><li>Mass is the amount of matter that something is made of. </li></ul><ul><li>Even atoms have mass! </li></ul><ul><li>Looking at the picture… </li></ul><ul><li>The mass stays constant in certain forms of matter such as…__________________. </li></ul><ul><li>The mass changes in certain forms of matter such as…_________________. </li></ul>
  7. 7. What is the difference between mass and weight? <ul><li>This is an important concept to understand! </li></ul><ul><li>Let’s start by understanding gravity. </li></ul><ul><li>Gravity is the force of attraction between objects that is due to their masses. </li></ul><ul><li>All matter experiences gravity! </li></ul><ul><li>The amount of attraction between two objects depends on their weight. </li></ul><ul><li>There is attraction between all objects with mass, but since they are so small in reference to the earth, the attraction between them is also small. </li></ul>
  8. 8. So, what about weight? <ul><li>Weight is the measure of the gravitational force exerted on an object! </li></ul><ul><li>Look at Spot and the rock…which one is attracted to the earth more through gravitational force? ________________ </li></ul><ul><li>Which one weighs more? ___________ </li></ul><ul><li>So, this means the greater the gravitational force, the greater the weight. </li></ul><ul><li>Which weighs </li></ul><ul><li>more? -------> </li></ul>
  9. 9. Measuring Weight and Mass <ul><li>The SI unit for mass is kilogram (kg). </li></ul><ul><li>Sometimes we will use milligrams or grams. (mg or g) </li></ul><ul><li>The SI unit for weight (or gravitational force) is NEWTONS. </li></ul><ul><li>A Newton is approximately equal to the weight of a 100 gram mass on earth. </li></ul>
  10. 10. The major differences between <ul><li>MASS </li></ul><ul><li>A measure of the amount of matter in object. </li></ul><ul><li>Always constant, no matter the location. </li></ul><ul><li>Measured with a balance. </li></ul><ul><li>Expressed in kilograms, grams, and milligrams. </li></ul><ul><li>WEIGHT </li></ul><ul><li>A measure of the gravitational force on an object. </li></ul><ul><li>Varies depending on where the object is in relation to the earth. Example: ____________ </li></ul><ul><li>Measured with a spring scale. </li></ul><ul><li>Expressed in Newtons. </li></ul>
  11. 11. Mass is a measure of Inertia <ul><li>What in the world is inertia? </li></ul><ul><li>Ever try to move a car? Yeah, it is difficult! </li></ul><ul><li>That is because of inertia! </li></ul><ul><li>Inertia is the tendency of all object to resist a change in motion. </li></ul><ul><li>This will cause objects that are still to remain still, and allow objects that are moving to continue moving. </li></ul><ul><li>Mass is a measure of inertia because the greater the mass of an object…the more difficult it is to move. </li></ul>
  12. 12. Describing Matter <ul><li>Knowing the characteristics or properties of an object can help you identify the object. </li></ul><ul><li>There are: </li></ul><ul><ul><li>Physical Properties </li></ul></ul><ul><ul><li>Chemical Properties </li></ul></ul>
  13. 13. Physical Properties <ul><li>Things that describe the object are physical properties. </li></ul><ul><li>Physical properties can also be observed or measured without changing the identity of the matter. </li></ul><ul><li>Examples of physical properties include: color, odor, size, state, density, solubility, melting point, etc… </li></ul>
  14. 14. Spotlight on Density <ul><li>Density is a very helpful physical property. </li></ul><ul><li>Density = mass per unit of volume or Density = mass/volume </li></ul><ul><li>Density is an excellent help in identifying substances because each substance has its own density. </li></ul>
  15. 15. If Density = mass/volume <ul><li>Then mass = volume x density </li></ul><ul><li>or </li></ul><ul><li>m = v x d </li></ul><ul><li>AND volume = mass/density </li></ul><ul><li>or </li></ul><ul><li>volume = m </li></ul><ul><li>V </li></ul>
  16. 16. Chemical Properties <ul><li>Chemical properties describe a substance based on its ability to change into a new substance with different properties. </li></ul><ul><li>Ex: wood burns to form ash and smoke </li></ul><ul><li>Chemical properties cannot be observed with your senses. </li></ul><ul><li>Chemical properties aren’t as easy to observe as physical properties. </li></ul><ul><li>Examples of chemical properties: flammability and reactivity </li></ul>
  17. 17. Characteristic Properties <ul><li>The properties that are most useful in identifying a substance are its characteristic properties. </li></ul><ul><li>Remember the difference between physical and chemical properties. </li></ul><ul><li>Physical properties can be observed! (with your eyes!) IDENTITY OF SUBSTANCE DOES NOT CHANGE! </li></ul><ul><li>You can observe chemical properties only in situations in which the identity of the substance could change. </li></ul>
  18. 18. Physical Changes <ul><li>A physical change is a change that affects one or more physical properties of a substance. </li></ul><ul><li>Physical changes do not form new substances! EX: ice melting or sugar dissolving </li></ul><ul><li>Physical changes are easy to undo. </li></ul>
  19. 19. Chemical Changes <ul><li>A chemical change occurs when one or more substances are changed into entirely new substances with different properties. </li></ul><ul><li>You can observe chemical properties only when a chemical change might occur! </li></ul><ul><li>Examples of chem. changes: </li></ul><ul><li>baking a cake </li></ul><ul><li>rusting </li></ul>
  20. 20. Clues to chemical changes <ul><li>Color change </li></ul><ul><li>Fizzing or bubbling (gas production) </li></ul><ul><li>Heat </li></ul><ul><li>Production of light, sound, or odor. </li></ul><ul><li>Chemical changes are not usually reversible! </li></ul>
  21. 21. For tomorrow… <ul><li>Please re-read Phyz talk </li></ul><ul><li>Be prepared to begin stations. </li></ul><ul><li>Know that I am going to do a binder check this week! </li></ul>