Properties of Matter: Elements, Compounds, & Mixtures

1. Chapter 2 Properties of Matter 2-1 Classifying Matter

2. Objectives • Classify pure substances as elements or compounds • Describe the characteristics of an element and the symbols used to identify elements • Describe the characteristics of a compound

3. Pure Substances • Matter that always has exactly the same composition is classified as a __________substance. • Every sample of a given substance has the same properties because a substance has a fixed, _______ composition. • Ex – Table ______ (Na) and _____(C6H12O6) • Can be classified into _______ and ______

4. Elements • ________ is a substance that cannot be broken down into simpler substances. • _________are the smallest particle of an element. • An element has a fixed composition because it contains only_______type of atom.

5. Examples of Elements • Most are ______– Aluminum (Al) • Some are _______– Carbon (C) • Two are liquids are room temperature – ________ (Br) and________ (Hg)

6. Symbols for Elements • The ______ letter is always capitalized • If there is a _______ letter it is not capitalized -Na (sodium) • If the symbol contains only one letter, it is _______ capitalized - C

7. Compounds • A _________ is a substance that is made from two or more simpler substances and can be broken down into those simpler substances. • A compound always contains ______or more elements joined in a fixed proportion. • Ex. Water – ______

8. Mixtures • The _________ of a mixture can vary because of composition of a mixture is not fixed. • Example - ________

9. Beaker Breaker!! 1.) Can an element or a compound be broken down into simpler parts? 2.) What is an example of a pure substance? 3.)What are the building blocks of elements?

10. What is a mixture? • Variable combination of____ or more pure substances. Heterogeneous Homogeneous

11. What is the difference between a homogeneous and aheterogeneoussubstance? • Heterogeneous: substance whose composition is ______ uniform throughout……always a __________

12. What is the difference between ahomogeneous and aheterogeneous substance? • Homogeneous: substance that is __________ (same) in its composition

13. A mixture may be… • Homogeneous • (______) • Heterogeneous • (________)

14. Solutions • When substances ________ and form a homogeneous mixture, the mixture that forms is called a_________. • Ex: ____ water and _________ wiper fluid • _______ passes through liquid solutions without being scattered in all directions

15. Suspensions • A heterogeneous mixture that ________ into layers over time is called a _________. • Ex: Shaking a jar of _______ and ______

16. Colloids • A________contains some particles that are intermediate in size between the small particles in solution and the larger particles in a suspension. • _______ is a colloid of water droplets in air • _________ of light is a property of a colloid

17. Beaker Breaker!! 1.) When substances dissolve and form a homogeneous mixture, the mixture that forms is called a___________. 2.) Is fog an example of a colloid or a suspension? 3.) A heterogeneous mixture that separates into layers over time is called a_____________

18. Solutions Cont. • Recall that a solution is a homogeneous mixture of two or more substances • Two components • _________ • _________

19. Solutes • A ________ is a substance whose particles are dissolved in a solution.

20. Solvents • The substance in which the solute dissolves is called the ________.

21. Example • _______ solution • Solute = ______ • Solvent = _______

22. Beaker Breaker!! 1.) A__________________is a substance whose particles are dissolved in a solution. 2.) The substance in which the solute dissolves is called the ___________________. 3.) sugar in water – circle the solvent and underline the solute

23. 2-2 Physical Properties • A _________ property is any characteristic of a material that can be observed or measured without changing the composition of the substances in the material

24. Examples of physical properties 1. 2. 3. 4. 5. 6. 7.

25. Viscosity • The tendency of a liquid to keep from flowing – __________ to flowing is called ________. • Example - ________

26. Conductivity • A material’s ability to allow _______ to flow is called _____________ • Example : Metals = ______ conductivity or also know as _________ • Stirring soup with a________spoon verses wooden spoon

27. Malleability • Malleability is the ability of a solid to be_________ without shattering. • Ex gold and ___________

28. Hardness • One way to compare the hardness of two materials is to see which of the materials can _________ the other. • Ex: Kitchen knife (stainless steel) scratching _________

29. Melting Point and Boiling Point • The temperature at which a substance changes from a _______to a ______ is its ________point. • The temperature at which a substance __________ is its _______point • Ex: _______ at 0 degrees Celsius and 100 degrees Celsius

30. Density • _______can be used to test the purity of a substance. • Density = Ex: Silver coin density = 9.9g/cm3 Actual density of silver = 10.5g/cm3 Coin is not _______silver

31. Beaker Breaker!! 1.) Name one of the seven physical properties________________ 2.) Which physical property is defined as a material’s ability to allow heat to flow? 3.) Aluminum and Gold are examples are what physical property?_____________

32. Using Properties to Separate Mixtures • ________ is a process that separates materials based on the size of their particles • ___________ is a process that separates the substances in a solution based on their _______ points.

33. Recognizing Physical Changes • A __________ change occurs when some of the properties of a material change, but the substances in the material remains the same. • Ex: slowly heating butter in a pan –changes from solid to liquid, but the substance in the butter remains the _________. • _________ a tomato • Crumpling a piece of paper

34. Chemical Properties • A ________ property is any ability to produce a change in the___________ of matter. • Chemical properties can be observed only when the substances in a sample of matter are ________ into different substances.

35. Examples • ___________ is a material’s ability to burn in the presence of oxygen. Ex. __________ and _________

36. Reactivity • The property that describes how readily a substance combines chemically with other substances is ____________. • Example – _________ in air ________ is highly reactive Nitrogen has a ______ reactivity - _______ is another example

37. Recognizing Chemical Changes • A ________ change occurs when a substance reacts and forms one or more _______ substances. Examples: cake ______ in oven leaves on trees change ____ food ________ in your stomach

38. Three common types of evidence • Change in _______ • The production of a ________ • The formation of a _________

39. A change in color • Ex: ________tarnishing a ________ burning then turning black and shrivels

40. Production of a Gas • Ex: Combining vinegar and baking soda – _________of carbon dioxide form

41. Formation of a Precipitate • Any __________that forms and separates from a liquid mixture is called a _____________. • Ex: when acid is added to _____, proteins in the milk undergo a chemical change that alters their structure, causing them to stick together in ___________

42. Is a change chemical or physical? • When matter undergoes a chemical change, the _________ of matter changes. • When matter undergoes a physical change, the composition of the matter remains the________.

43. Beaker Breaker!! 1.) What is one of the three common types of evidence of a chemical change? 2.) Any solid that forms and separates from a liquid mixture is called a__________ 3.) Gasoline and paper is an example of what chemical property?