1. Chapter 2 Matter and Change
Hingham High School
Mr. Clune

2. What is Matter? Matter is anything that takes up space and has mass.
Mass- amount of material or “stuff” in an object
Weight is due to gravity, and changes from location to location; mass is always constant.

3. Mass or Weight

4. Types of Matter
Substance- a particular kind of matter - pure; is uniform (all the same) and has a definite composition (examples are elements & compounds)
water; gold; lemonade?
Mixture- more than one kind of matter; has a variable composition

5. Substance or Mixture???

6. Properties Words that describe matter (adjectives)
Physical Properties- a property that can be observed and measured without changing the composition.
Examples- color, hardness, m.p., b.p.
Chemical Properties- a property that can only be observed by changing the composition of the material.

7. Properties Words that describe matter (adjectives)
Physical Properties- a property that can be observed and measured without changing the composition.
Examples- color, hardness, m.p., b.p.
Chemical Properties- a property that can only be observed by changing the composition of the material.

8. Properties????

9. States of matter
Solid- matter that can not flow (definite shape) and has definite volume.
Liquid- definite volume but takes the shape of its container (flows).
Gas- a substance without definite volume or shape and can flow.
Vapor- a substance that is currently a gas, but normally is a liquid or solid at room temperature. (water vapor?)

10. States of matter

11. States of Matter Definite Volume? Definite Shape? Temp. increase
Com-pressible?
Small Expans.
Solid
YES
YES NO
Small Expans.
Liquid NO NO
YES
Large Expans.
Gas NO NO
YES

12. Condense
Freeze
Melt
Evaporate
Solid
Liquid
Gas

13. Physical Changes
A change that changes appearances, without changing the composition.
Ex. Boil, melt, cut, bend, split, crack
Boiled water is still water.

14. O2 + Fe Fe2O3 Chemical Changes
Chemical changes - a change where a new form of matter is formed.
Ex. Rust, burn, decompose, ferment
O2 + Fe Fe2O3

15. Mixtures
Physical blend of at least two substances; variable composition
Heterogeneous- mixture is not uniform in composition
Chocolate chip cookie, gravel, soil.

16. Mixtures
Homogeneous- same composition throughout; called “solutions”
Kool-aid, air, salt water
Every part keeps it’s own properties.

17. Mixtures
Heterogeneous
Homogeneous

18. Solutions
Homogeneous mixture
Mixed molecule by molecule
Can occur between any state of matter
gas in gas; liquid in gas; gas in liquid; solid in liquid; solid in solid (alloys), etc.

19. Solutions
Like all mixtures, they keep the properties of the components.
Some can be separated easily by physical means: rocks and marbles, iron filings and sulfur
Other methods: distillation- takes advantage of different boiling points

20. Distillation

21. Filtration

22. Water Filtration

23. Homework
Worksheets
Section 2-1
Section 2-2

24. Section 2.3 Elements and Compounds

25. Substances Hg Cu H Au
NaCl
H2O
CO2
Elements
Compounds

26. Elements
Element
A pure substance that cannot be made simpler by known chemical means
Examples: hydrogen, oxygen, nitrogen, carbon, phosphorus, sodium, potassium and chlorine

27. Elements
Each element is represented by a symbol that usually consists of one or two letters
Hydrogen (H), Oxygen (O), Carbon (C), Chlorine (Cl), Sodium (Na)

28. Pure substances produced from the chemical combination of elements
Compounds
Pure substances produced from the chemical combination of elements
Examples: water (H2O) is a compound of hydrogen and oxygen, sodium chloride (NaCl) is a compound of sodium and chlorine.

29. Compounds Has a fixed composition
Has its own characteristic properties
H2 is a combustible gas, O2 is a gas helps burning but H2O is a liquid that is used to extinguish fire.

30. Compound or Mixture Compound Mixture Made of one kind of material
Made of more than
one kind of material
Made by a
physical change
Made by a
chemical change
Definite
composition
Variable
composition

31. Which is it?
Mixture
Compound
Element

32. Chemical Symbols & Formulas

33. Chemical Symbols & Formulas
Currently, there are 116 elements
Each has a 1 or two letter symbol
First letter always capitalized; the second never; chemical “shorthand”
Some from Latin or other languages;

34. Practice Problems: 18,19 Page 51 Section Assessment 20-27 Page: 52
Homework 2.3
Practice Problems: 18,19
Page 51
Section Assessment
20-27
Page: 52
Due: 9/24/04

35. Chemical Reactions
Yields
H H2 + O2
Reactants }
Products }

36. Chemical Reactions
When one or more substances are changed into new substances.
Reactants- stuff you start with
Products- What you make

37. Chemical Reactions
Ability to undergo chemical reaction is called a chemical property
Products have NEW PROPERTIES
Arrow from reactants to products

38. Indications of a chemical reaction:
Energy absorbed or released (temperature changes hotter or colder)
Color change
Gas production (bubbling, fizzing, or odor change)

39. Indications of a chemical reaction:
Formation of a precipitate- a solid that separates from solution (won’t dissolve)
Irreversibility- not easily reversed

40. Law of Conservation of Mass
Mass can not be created or destroyed in ordinary (not nuclear) chemical reactions or physical change

41. Law of Conservation of Mass
All the mass can be accounted for.
Burning of wood results in products that appear to have less mass as ash; where is the rest?

42. Law of Conservation of Mass
H H2 + O2 2 2
Products }
Reactants }
10g
10g

43. Homework
Worksheets 2.3 & 2.4
Due: 9/20/05
Test: 9/21/05