2. Matter

3. Anything that exists that has definite MASS and occupies a definite VOLUME Matter can be classified as pure substances or mixtures

4. Matter Mixture Pure Substance Element Compound Heterogeneous Mixture Homogeneous Mixture Can be separated physically Cannot be separated physically Can see the parts Cannot see the parts Can be separated chemically Cannot be separated Most impure Most pure

5. Pure substances are defined as substances that are made of only one type of atom or only one type of molecule (a group of atoms bonded together). Are uniform (all the same throughout) and have definite composition Ex: CO, H 2 O, N 2, Pb, C Pure substances can be divided into 2 categories: elements and compounds 1. Pure Substances

6. Elements – Substances made up of only one type of atom. - Cannot be separated by any physical OR chemical process. - all elements are listed on the periodic table of elements Examples: Carbon Helium Gold Elements

7. Elements are the simplest form of matter. Everything in the Universe is made of elements. Hydrogen makes up 99% of the Universe.

8. Diatomic Elements The smallest part of an element is an atom. Some elements have atoms that are always arranged in pairs.(di = two, atomic = atom). Since they are made of only one element, they are not considered to be compounds. Elements that are diatomic: H, N, O, F, Cl, Br, I* and At* (*as gases)

9. Monoatomic Element Elements that exist as single atoms, not bonded to each other.

10. Molecule Formed when two or more atoms join together chemically. Ex: N 2, H 2, O 2, H 2 O, CO

11. Compounds – Two or more elements chemically bonded together that can be separated only by a chemical reaction Examples: Carbon Dioxide (CO 2 ) Water (H 2 O) Salt (NaCl) Sucrose (C 12 H 22 O 11 )

12. Compound Compounds have a fixed composition. The amount of each element in a compound is always the same ratio. In water, the ratio of H:O is always 2:1. All compounds are molecules but not all molecules are compounds. Ex: H 2 = molecules not compound H 2 O = molecule and compound

13. 2. Mixtures Mixture – Two or more pure substances mixed together. Each substance in the mixture retains its own set of chemical and physical properties. Example: Copper and Zinc can be mixed together to produce brass. Even though it may look different, it is still copper and zinc. Each metal retains its own properties like melting point.

14. Classification of Matter Unlike pure substances, mixtures can always be separated by physical means. How could we separate the copper and zinc back out? mixtures have no fixed composition. The amount of one or more components (substances) can usually vary over a wide range

15. Mixtures Some mixtures are more pure than others. Heterogeneous mixture – Uneven distribution of substances. (Very impure) - You can see the different parts. Examples: Sand Granite Wood Milk Blood

16. Mixtures Homogeneous Mixture – Components are evenly mixed. (More pure than heterogeneous) -Cannot see the parts Example: solutions - salt water, soda pop, tea, alloys* and clean air. *Alloys are mixtures of metals: steel (Fe & C), 14K gold (Au & Cu), Bronze (Cu & Sn)* -

17. Matter Mixture Pure Substance Element Compound Heterogeneous Mixture Homogeneous Mixture Can be separated physically Cannot be separated physically Can see the parts Cannot see the parts Can be separated chemically Cannot be separated Most impure Most pure

18. Checking for understanding Explain in your own words:  Element  Monoatomic element  Diatomic element  Molecule  Pure substance  Compound Circle the diatomic elements:  K He Cl P N O U Br  F Na Li H C At Ne I

19. 189/30/2016 Which is it? Element Compound Mixture

20. 199/30/2016 Checking For Understanding Identify the matter below as a substance or mixture. If it’s a mixture identify it as a solution or heterogeneous mixture. 1) sugar water 2) blood 3) CO 2 4) ink Mixture- solution Mixture- hetero Substance Mixture- hetero

21. 209/30/2016 Checking For Understanding Identify the matter below as either a compound, element, solution or heterogeneous mixture. a) carbonated water b) tap water c) Italian salad dressing d) bronze e) zinc metal f) carbon monoxide, CO solution heterogeneous solution element compound

22. Phases of Matter

24. Solids The particles in a solid are held together in an orderly fashion with little freedom of motion – back and forth vibration Most solids are composed of atoms arranged in a crystalline lattice - a repeating network of particles. Properties: a.Have a definite shape & definite volume b. Are usually the most dense phase of a substance. Water is one exception. c.Of the 4 phases, solids have the least amount of heat energy.

25. Solids – Crystalline Lattice A crystalline lattice is made of unit cells. A unit cell is composed of the repeating two or more atoms that make up the crystalline lattice. A unit cell in the above crystalline lattice would be composed of two atoms:

26. Snowflakes are a good example of a crystalline solid. The growing crystalline lattice makes a unique geometric shape - no two flakes are alike.

27. Liquids When a solid is heated to it’s melting point, the crystalline lattice breaks apart - forming a liquid. The particles in a liquid not held together in a rigid pattern and can move past one another. The particles in a liquid are still close together. This is the reason why both solids and liquids are not compressible but gasses are.

28. Liquids Properties: a.Have a definite volume but no definite shape. b.Are usually less dense than solids, but more dense than gases. c.Have particles that are free to about. d.Produced by heating a solid to its m.p.

29. Viscosity of Liquids Viscosity is the resistance of a liquid to flow. The more resistance to flow, the higher the viscosity. Viscosity of Liquids Motor Oils protect an engine from wear and tear due to friction between moving parts. Motor oils are rated by their viscosity. A motor oil of 10W-40 means it has a viscosity of 10 (low) in the winter and 40 (high) in the summer. The higher the temperature inside the engine- the higher the viscosity of the oil required.

34. Gases Gases take up much more space than solids or liquids. This is proof that particles in a gas are far apart, while those in a solid or liquid are close together. Properties: a.Have no definite volume or shape. b.Are less dense than solids & liquids. c.Have particles that are free to move in all directions - hence they take up all available space in a container. d.Can be easily compressed since the particles are separated by great distances.

36. Plasma Plasma is the 4th phase of matter. Plasma occurs when matter is heated to extremely high temperatures. Atoms lose electrons & become charged particles. Stars are made of plasma as is lightning. Over 99.9% of the universe is plasma.

38. 379/30/2016 Solid Liquid Gas Melt Evaporate Condense Freeze Sublime Deposit

39. Checking for understanding Compare the 3 phases of matter SolidLiquidGas Definite shape Definite volume Arrangement of particles

40. Changes and Properties of Matter

41. Physical Properties of Matter Physical Changes: Changes that change only the appearance of a substance, not its chemical identity. Physical Properties: Properties that can be observed through physical change

42. Physical Change Melting Boiling Dissolving Evaporating Crushing Stretching Physical Property Melting point (the temperature at which a substance turns from a solid to a liquid) Boiling point (the temperature at which a substance turns from a liquid to a gas) Solubility (the amount of solute that can be dissolved in a solvent) Vapor pressure (the pressure exerted by a vapor at vapor-liquid equilibrium) Malleability (the ability to be hammered or rolled into thin sheets) Ductility (the ability to be stretched into a wire) Density (the mass of a substance per unit volume) Electrical & Heat Conductivity (the ability to pass heat or electricity through a substance

43. Chemical Properties and Changes Chemical Changes: Changes that result in changing the chemical composition of a substance. Can be reversed only by another chemical change. Chemical Properties: Properties that can only be observed through chemical change.

44. Chemical Change Corrosion of metals, flammability Chemical decomposition e.g. hydrogen peroxide decomposes to form water and oxygen, but water does not decompose spontaneously Combustion releases heat (exothermic) Rarely do chemical changes absorb heat (endothermic) Chemical Property Reactivity (the likelihood of one substance to undergo a chemical reaction with another substance) Stability (the likelihood that a substance will no decompose) Heat of Reaction (the energy absorbed or released by a chemical reaction)

45. 449/30/2016 Indications of a chemical reaction: Energy absorbed or released ( heat and/or light ) Color change Gas production (bubbling, fizzing, or odor change) formation of a precipitate- a solid that separates from solution (won’t dissolve) Irreversibility- not easily reversed new substances produced, old substances destroyed.

46. Checking for understanding Explain why are these processes physical changes: Boiling Condensation Shredding paper Explain why are these processes chemical changes: Burning paper Rusting bicycle Frying eggs

47. Density

48. D = m/v m = Mass, in grams v = Volume, in cm 3 or liters, etc. D= density, in g/cm 3 Density = amount of matter per unit volume – Density is the measure of the “compactness” of a material – How close the atoms or molecules are to each other – More than “heaviness” - density includes how much space an object takes up!! – All substances have density including liquids, solids, and gases Density is the ratio of mass to volume

49. Calculate Density A piece of wood has a mass of 11.2 g and a volume of 23 mL what is the density?

50. Calculate Density A piece of wood has a density of 0.93 g/mL and a volume of 23 mL what is the mass?

51. 509/30/2016 A solid displaces a matching volume of water when the solid is placed in water. 33 mL 25 mL Volume Displacement

52. 51 9/30/2016 What is the density (g/cm 3 ) of 48 g of a metal if the metal raises the level of water in a graduated cylinder from 25 mL to 33 mL? 1) 0.2 g/ cm 3 2) 6 g/cm 3 3) 252 g/cm 3 33 mL 25 mL Volume Displacement

53. 52 9/30/2016 2) 6 g/cm 3 Volume (mL) of water displaced = 33 mL - 25 mL = 8 mL Volume of metal (cm 3 ) = 8 mL x 1 cm 3 = 8 cm 3 1 mL Density of metal = mass = 48 g = 6 g/cm 3 volume 8 cm 3 Volume Displacement

54. 53 9/30/2016 Density Which diagram represents the liquid layers in the cylinder? (K) Karo syrup (1.4 g/mL), (V) vegetable oil (0.91 g/mL,) (W) water (1.0 g/mL) 1) 2) 3) K K W W W V V V K Ta-dah!