INTRODUCTION TO MATTER

1. INTRODUCTION TO MATTER

2. MATTER • Anything that has mass and volume • Is everything around you • Everything on the Periodic Table • All solids, liquids, gases, etc.

3. Identifying Matter • Matter can be identified by its properties (characteristics) • Some properties are shared by lots of matter • Some properties are unique and used to identify different types of matter = CHARACTERISTIC PROPERTIES

4. Physical Properties • Physical Properties are properties that you can observe without changing the identity of the substance • Examples: color, shape, size, mass, weight, state, boiling and freezing points, magnetism, tensile strength (stretch), viscosity (flow), malleability (pounded into sheets), density

5. PHYSICAL Properties • Specific: CAN be used to identify an object, unique or “special” • Describes how forms of matter are DIFFERENT • Color, shape, size, texture, odor, and hardness • General: NOT enough detail to identify object • Describes how forms of matter are the SAME • Mass, weight, volume, density

6. SPECIFIC vs. GENERAL • The stone is smooth and round • The lemon is yellow and taste sour • The dog is 8 kgs • We went to the store and bought a 5 Newton bag of charcoal • I asked the store clerk for 1 liter of H2O • Cork is less dense than water, which is why it floats

7. SPECIFIC vs. GENERAL (cont.) • Ice is cold and hard • The liquid in the bottle had a strange odor • The square sheet of paper is red on one side and white on the other • The 100 gram piece of metal just balances the rock on the scale

8. ARE DIFFERENT FORMS OF MATTER SIMILAR IN ANY WAY? • Distinguish between matter via properties • Property is a characteristic or description of an object • There are two types of properties/changes • Physical and Chemical • Based on studying chemical reactions and states of matter

9. Physical Change • Change that does NOT affect an object’s identity • Examples: • Breaking into pieces, changing shape, freezing, melting, boiling * Can usually be reversed

10. When substances changes states, their identity does not change. As of 1995, 5 states of matter have been identified 1. solid 2. liquid 3. gas 4. plasma 5. Bose-Einstein Condensates

11. CHEMICAL • A chemical change is a a change that does affect an object’s identity • Happen on a molecular level (i.e. small scale) • Some changes are obvious, others are not • Color change • Formation of a new chemical • Rust • Burning • Original product you start out with ceases to exist; formation of a new and different product

12. Chemical Properties • CHEMICAL Properties are properties that indicate whether an object can undergo a chemical change. • Chemical properties cannot be tested with out changing the substance chemically • Examples: • Flammable • Corrosive • Explosive • Light sensitive • Heat sensitive

13. CHEMICAL • Chemical changes are also called Chemical reactions, involve the changing of one substance into another • Examples: rusting, burning, digesting, cooking, photosynthesis, etc • Chemical changes usually CANNOT be reversed

14. Chemical Changes cont. • How do you know chemical reaction has taken place? • Color change • Temperature change • Gas produced (bubbles) • Precipitate forms • When a chemical reaction takes place the mass NEVER changes. The mass of the products always equals the mass of the reactants. • Law of Conservation of Mass

15. MASS vs. WEIGHT • Mass • Anything that has matter and takes up space • Does NOT change with location • Measured in grams with a balance

16. MASS vs. WEIGHT (cont.) • Weight • The force of gravity on an object • DOES change with location • Measure in Newtons (N) with a scale • Weight = mass (gravity) • Gravity (on Earth) = 9.8 m/sec2 • Gravity on moon = 1.6 m/sec2 • Gravity on Jupiter = 24.8 m/sec2

17. MASS vs. WEIGHT (cont.) • 3 differences between the two • They differ by definition • Weight is a value that changes and depends on location. Mass is a value that remains constant unless matter is added or taken away • They differ in their respective measured units • Weight is measure in Newtons (N) • Mass is measured in grams (g)

18. DENSITY • Is the mass per unit of volume of a substance • Mass is the amount of matter in an object • Volume is the amount of space an object takes up • If two objects are the same size, the heavier one is more dense • Density = mass/volume • Units are g/mL or g/cm3

19. DENSITY (cont.) mass density volume

20. C. Derived Units Combination of base units. Volume - length  length  length 1 cm3 = 1 mL 1 dm3 = 1 L Density - mass per unit volume (g/cm3) M V M D = D V

21. D. Density An object has a volume of 825 cm3 and a density of 13.6 g/cm3. Find its mass. M D V GIVEN: V = 825 cm3 D = 13.6 g/cm3 M = ? WORK: M = DV M = (13.6 g/cm3)(825cm3) M = 11,220 g

22. D. Density 1) A liquid has a density of 0.87 g/mL. What volume is occupied by 25 g of the liquid? WORK: V = M D V = 25 g 0.87 g/mL M D V GIVEN: D = 0.87 g/mL V = ? M = 25 g V = 28.7 mL

23. D. Density 2) You have a sample with a mass of 620 g & a volume of 753 cm3. Find density. WORK: D = M V D = 620 g 753 cm3 M D V GIVEN: M = 620 g V = 753 cm3 D = ? D = 0.82 g/cm3

24. DENSITY (cont.) • Density of an object will determine is the object will float or sink • If an object floats in a fluid, the density of that object is less than the fluid’s density • If an object sinks in a fluid, the density of that object is greater than the fluid’s density • Density of water is 1.0 g/mL

25. DENSITY (cont.) • An unknown substance has a mass of 36.4g and a volume of 10mL. What is the density? • A substances has a mass of 62.55g and a volume of 4.8cm3. What is the density of the substance? • A piece of steel has a mass of 35g and a density of 7.8g/cm3. What is the volume of the steel? • A substance has a density of 19.3 g/mL and a volume of 2.45 mL. What is the mass of the substance?