1. Chapter Two Properties of Matter

2. Matter Pure Substance ElementCompoundMixture Homogeneous mixture Solution Heterogeneous mixture ColloidSuspension Classification of Matter

3. Matter Is anything that has mass and takes up space

4. In its most basic distinction, matter can be classified as either a pure substance or a mixture. Matter Pure Substance Mixture

5. Pure Substance Like the name suggests, a pure substance is made of one type of material. It cannot be broken down into a simpler form without losing its identity. Pure substance Element (only made of atoms) Compound (made of molecules, groups of atoms chemically combined)

6. Elements Elements are the simplest form of a pure substance. They are only composed of atoms of that element. Gold is only made up of gold atoms. Chlorine is only made up of atoms of chlorine. Sulfur is only made up of atoms of sulfur.

7. Elements Prepare for Element Quizzes!!!!!! You will know them inside and out!!! Elements

8. All atoms of an element are identical to each other but completely different from atoms of any other element. Each atom of a given element has a unique number of protons in its nucleus. This determines the identity and the properties of that element. Every element is identified by a chemical symbol, a 1,2,or 3 letter symbol taken from the element’s name (Latin), country of origin, or the person who discovered it. – There have been over 120 identified elements, 92 of which are naturally occurring. Elements cannot be broken down into any simpler substance. Properties of Elements

9. Daily Assignment Explain why both elements and compounds are considered pure substances. Each are only made up of only one type of substance. Elements are composed of atoms of that element. Compounds are composed of molecules of that compound.

10. Compound Are formed from the chemical combination of two or more elements. To create a compound, a chemical change ( or reaction) must take place in which a new substance with a new set of properties is formed. Sodium + Chlorine Sodium Chloride

11. Properties of Compounds Chemically combined groups of elements are called molecules, represented by a chemical formula. – The formula tells you the identity of the elements and the number of atoms of each element in that compound. NaCl H20 NH3 Each molecule of a given compound is identical to every molecule of that compound, but completely different from molecules of a different compound. The properties of the compound are different than the properties of the elements that make it up. – NaCl is table salt. It is formed by the chemical combination of Na, a silver metal that explodes in water and Cl, a poisonous green gas. – Sucrose (C12H22O11 ) is table sugar. However, Carbon is a black solid and hydrogen and oxygen are both colorless, odorless gases.

12. Compounds The ratio of different atoms in a compound is always the same. Hydrogen and oxygen can combine in different ratios to form different compounds. Compounds cannot be broken down into simpler substances that still retain the properties of that compound. H2OH2O H2O2H2O2

13. Daily Assignment Copper, Sulfur, and oxygen combine to create Copper sulfate. How do you know that copper sulfate is a compound?

14. Mixture Matter that consists of two or more substances that are mixed together but not chemically combined is a mixture. Mixtures are physically combined. Mixtures “together but separate”

15. Mixtures Each substance that makes up a mixture retains its chemical / physical properties. Sulfur = yellow, rotten egg smell Iron = black, magnetic Even in a mixture, iron is still magnetic. Iron in the compound FeS is NOT magnetic.

16. Mixtures The substances that make up a mixture may be present in any amount, unlike compounds which must combine in specific ratios. It doesn’t matter how much koolaid you mix with the water, it is always a koolaid and water mixture.

17. Mixtures Since mixtures are physically combined they can also be separated based on the physical properties of their components. How would you separate these mixtures? Ocean water Beach sandTrail mix

18. Separation of Mixtures

19. Mixtures Mixtures can be further distinguished as either a homogeneous mixture or a heterogeneous mixture. Mixtures Homogeneous mixture Heterogeneous mixture

20. Homogeneous Mixture A.K.A. a solution. “Homo” means the same. A homogeneous mixture appears to have the same properties throughout the entire mixture. A solution is formed when substances are dissolved in another substance. The particles that make up a solution are very small. They will never settle to the bottom. PURE AIR

21. Heterogeneous Mixture Is a mixture that appears to have “different” properties throughout the mixture. The particles that make up a het. mixture are larger then those that make up a solution. Heterogeneous mixture ColloidSuspension

22. What kind of mixtures are these?

23. Colloid The particles that make a colloid are mixed, but not dissolved. These particles are larger than those in a solution, but they will never settle to the bottom. Due to their large particle size, a colloid often appears cloudy. colloid Mayonnaisepaint milk smog Jello and whipped cream

24. Suspension Are the least mixed of all the mixtures. These are made of the largest size particles. If you let a suspension sit long enough, it’s particles will settle to the bottom. suspension Cookie dough ice cream Cereal and milk Muddy pond water

25. Tyndall Effect Is the effect of a laser to pass through a mixture. If the laser passes through completely, the mixture is a solution. If the laser is trapped (or bounced between particles) it is a colloid or suspension. Light passes through the blue solution. Particles of a colloid scatter the light

26. Physical Properties A physical property is a characteristic of material that you can observe without changing the identity of the substances that make up the material. Examples: color, shape, size, density, melting/freezing/boiling point, texture, magnetism, and viscosity.

27. Physical Properties Viscosity – the tendency of a liquid to resist flow Conductivity – the ability of a substance to carry electrical current Malleability – the ability of a substance to bend without breaking Hardness – How hard something is Melting and Boiling Points

28. Physical Properties Density – ratio of a substance’s mass to its volume Two ways to separate mixtures – Filtration – using some kind of medium to remove large particles – Distillation – boiling out the pure substance

29. Physical change A change is the size, shape or state of matter. change The identity of the materials that makeup the substance is never altered during a physical change.

30. Chemical Property A chemical property is a characteristic of a material that you can only observe by changing the identity of the substance. flammability Photosensitivity Oxidation (rust) combustibility

31. Chemical Properties Flammability – the readiness with which a material burns Reactivity – the likelihood of something reacting with another chemical Chemical Properties

32. Chemical Change A changing of one substance to another is a chemical change. You cannot return to the original substance after a chemical change. Fizzing and bubbling indicate chemical change. Cooking is a chemical change Electrolysis: separation of water

33. Chemical Changes Evidence of a chemical change chemical change – Change in color – Production of a Gas See Demonstration – Formation of a Precipitate See Demonstration

34. Chemical Vs. Physical In a chemical change, the substance changes. In a physical change, the matter remains the same.