1. Unit 2: Matter

2. Matter Anything that has mass and takes up space (volume) Matter resist change (inertia) Matter has the capacity to do work (energy)

3. Law of Conservation of Matter Matter is neither created or destroyed in a chemical reaction. Also referred to as the Law of Conservation of Mass

4. Physical Property Can be observed with the senses or measured without changing the substance Examples: Melting point Boiling point Color/shape Density Mass

5. Physical Properties can be Extensive Depends on the amount of matter Mass Length Volume Time to boil Intensive Does not depend on amount of matter Density Color Boiling point Melting point

6. Physical Change A change that does not involve altering the identity of the substance Examples: Freezing Melting Boiling Cutting Grinding

7. Chemical Property Relates to a substance’s ability to undergo a change into a different substance Examples: Ability to rust Flammable Ability to react with an acid Decomposes in light

8. Chemical Change A change where one or more substances is converted into different substances (a chemical reaction) Examples: Rotting Burning Fermenting Cooking

9. 4 indicators of a chemical change Color Change Evolution of heat or light Production of gas Formation of a precipitate

10. Precipitate: A solid that forms from solution

11. Chemical change = chemical reaction and is written as Reactants  Products This is what you start with This is what you end with

12. Classifying Matter Matter ElementsCompoundsMixtures Scientists classify matter according to make-up.

13. Elements Simplest pure substance – fixed composition. Pure substance is made of only one material. Same throughout. Referred to as homogeneous matter. Are made of alike atoms, which are the basic building blocks of matter. Represented by chemical symbols - H, O, Al, Cu, Au. 118 elements organized in the periodic table in squares called an element key.

14. Compounds Two or more elements chemically combined. Represented by chemical formulas. Examples: H 2 O, CO 2, NaCl, C 12 H 22 O 11 Molecules are the smallest natural unit of a compound or diatomic element. A molecule is made up of two or more atoms chemically combined.

15. MixturesMixtures Two or more substances mixed together but not chemically combined. Has unlike parts and a composition that varies from sample to sample. Properties: – Sub. in a mixture keep their separate identities. – Sub. can be present in any amount. – Sub. can be separated out by physical means.

16. Materials Mixtures Matter that contains more than one material Homogeneous Homogeneous Heterogeneous Heterogeneous Pure Substances One part is representative of the whole Element Element Compound Compound

17. Mixtures: Variable combination of two or more substances: Homogeneous uniform throughout Heterogeneous not uniform throughout

18. Mixtures HomogeneousHeterogeneous

19. Elements and Compounds An element is the simplest form of matter and has a unique set of properties. A compound contains two or more elements chemically combined in fixed proportions. Compounds can be broken down, elements cannot.

20. Pure Substances: Elements are Composed of identical atoms Chlorine gas Sodium metal

21. 2 or More Elements Combine to Produce a Compound Chlorine gas + Sodium metal + = = Sodium Chloride

22. Used to describe any part of a sample with uniform composition and properties Used to describe any part of a sample with uniform composition and properties Heterogeneous: 2 or more phases Heterogeneous: 2 or more phases Homogeneous: 1 phase Homogeneous: 1 phase Phase

23. The distinction between solutions and heterogeneous mixtures can be difficult especially in the liquid phase.

24. Solutions A homogeneous mixture. One substance dissolves in another. Solutions remain constantly & uniformly mixed. Solute and Solvent Particles are smaller than 1 nm in size Particles do not settle Particles pass through filter paper Examples: lemonade, soda, ocean water, antifreeze, metal alloys

25. A homogeneous mixture combining two or more metals to maximize the benefits of each. A homogeneous mixture combining two or more metals to maximize the benefits of each. Ex. Gold Jewelry: 14 kt Gold (Gold for shine, Silver for strength) Ex. Gold Jewelry: 14 kt Gold (Gold for shine, Silver for strength) Alloy

26. ColloidsColloids A homogeneous mixture. Mixed together but not dissolved. Appears cloudy. Scatters light. Particles are 2 – 100 nm in size Particles do not settle Particles pass through filter paper Usually not transparent (cloudy) Examples: milk, cool whip, toothpaste, lotions, fog, smoke, Jello.

27. Heterogeneous Mixture Heterogeneous Mixture Particles settle to the bottom unless constantly stirred Particles settle to the bottom unless constantly stirred Particles are greater than 100 nm Particles are greater than 100 nm Not transparent, must be mixed Not transparent, must be mixed Ex: Paint, Chocolate Milk, Ex: Paint, Chocolate Milk, Suspension

28. Composition of Matter

29. Separating Mixtures

30. Filtration Separates a solid from a liquid in a heterogeneous mixture Separates a solid from a liquid in a heterogeneous mixture Mixture passes through filter paper Mixture passes through filter paper Can sieve for larger pieces Can sieve for larger pieces Filter paper for finer pieces or powders Filter paper for finer pieces or powders

31. Distillation A liquid is boiled to produce a vapor, which is then turned back into a liquid through a condensation tube. A liquid is boiled to produce a vapor, which is then turned back into a liquid through a condensation tube. Substances that dissolve in water remain in flask Substances that dissolve in water remain in flask

32. Decanting After solid settles to bottom of container, the liquid is carefully poured off the top After solid settles to bottom of container, the liquid is carefully poured off the top

33. Chromatography Way to separate mixtures Way to separate mixtures General Chemistry Online General Chemistry Online General Chemistry Online General Chemistry Online Chromatography Web Animation Chromatography Web Animation Chromatography Web Animation Chromatography Web Animation

34. Centrifuge Separates solid from solution by spinning and pushing the solid to the bottom of the container Separates solid from solution by spinning and pushing the solid to the bottom of the container