1. Matter – Properties and Changes
Chapter 1
Matter – Properties and Changes

2. Properties of Matter Section 2

3. Definitions Mass – a measure of the amount of a substance
Matter – anything that has mass and takes up space

4. Building blocks of matter
Atoms – smallest unit of an element that maintains the identify of the element
Element – a pure substance that cannot be broken down into simpler, stable substances; made of one type of atom

5. Building blocks of matter
Compound – substance that can be broken down into simple stable substances; made of two or more elements that are chemically combined

6. Characteristic properties
Property – characteristic that defines/classifies a group of substances; can be used to identify unknown substances

7. Characteristic properties
Extensive properties – depend on the amount of matter present (volume, mass, amount of energy)
Intensive properties – do NOT depend on the amount of matter present (melting point, boiling point, density, electrical conduction)

8. Physical Properties
Characteristics that can be observed or measured without changing the sample’s composition
Ex: density, color, odor, taste, hardness, melting point, boiling point
NaCl
Solid, white RT, salty taste

9. Physical Changes Alter the substance WITHOUT changing the composition
Terms: bend, grind, crumple, split, crush, phase changes (melt, boil, freeze, condense, vaporize)

10. States of Matter
Solid
Liquid
Gas
plasma

11. Solid Definite shape Incompressible Definite volume
Tightly packed matter
Expand when heated

12. Liquid Flows Incompressible Constant volume Expands when heated
Takes shape of container
Particle able to move past each other

13. Gas Easily compressed Particles are very far apart
Fills entire volume of its container
Flows to conform to container shape

14. Plasma
High-temperature physical state of matter in which atoms lose most of their electrons

15. Chemical Properties
Ability of substance to react or not react with another substance
Ex: oxidizing (reacting with O2)
Fe reacts with O2 to make Fe2O3; but does not react with N2

16. Properties of Cu Physical Properties Reddish brown, shiny
Easily shaped into sheets (malleable)
Easily drawn into wire (ductile)
Good conductor of heat & electricity
Density = 8.92 g/ml
mp = 1085 °C
bp = 2570 °C
Chemical Properties
Forms green copper carbonate compound when in contact with moist air
Forms new substances when combined with nitric acid and sulfuric acid
Forms a deep blue solution when in contact with ammonia

17. Chemical Changes
Ability of substance to combine with or change into one or more substances
New substances have different compositions and properties than original substances
Terms: explode, rust, oxidize, corrode, tarnish, ferment, burn, rot

18. Chemical changes Also known as chemical reactions
Substances that react are REACTANTS
Substances that are formed are PRODUCTS

19. Law of conservation of energy
Energy is always involved with changes, physical OR chemical
Total amount of energy remains the same; energy is NOT created or destroyed
Energy may take a different form

20. Vapor vs. Gas
Vapor refers to a gaseous state of a substance that is solid or liquid at room temp
Gas refers to a substance that is naturally at the gaseous state at room temp

21. Classify each of the following as physical or chemical property
Fe and O form rust
Chemical
Fe is more dense than Al
Physical
Mg burns brightly when ignited
Oil and water do not mix
Hg melts at -39 °C

22. Law of Conservation of Mass
Mass cannot be created nor destroyed during a chemical reaction – it is conserved
Mass reactants = mass products

23. Mixtures 2 or more substances (compounds) are combined
Retains individual chemical properties
Most substances will mix
Difficult to keep things pure

24. Types of Mixtures Homogeneous mixture Heterogeneous mixture
uniform composition throughout
Also called solutions
Ex: salt water
Heterogeneous mixture
Does not blend well
Individual substances remain distinct
Ex: sand and water

25. Separating Mixtures Filtration Distillation Crystallization
Uses a porous barrier separate solid and liquid
Distillation
Differences in boiling points of substance
Crystallization
Results in formation of pure solid particles contained in the dissolved substance
Chromatography
Separates mixture based on ability to be moved across surface

26. Pure substances Has a fixed composition
Can be a compound or an element
Are always homogenous
But differ from mixtures by
Every sample has exactly the same characteristic properties
Every sample has the exact same composition

28. Elements & Compounds
Section 1.3

29. Elements Pure substance Cannot be further separated
91 naturally occurring elements
Ex: Cu, O, N, H
Remainder are made in the lab
Located on the Periodic Table
Developed by Dmitri Mendeleev

30. Periodic table Organizes elements based on chemical properties
Each box has the element symbol and its atomic number
Some symbols are based on English names, others are based on Latin or German names

31. Periodic table Vertical columns are groups or families
They are numbered 1 through 18 (left to right)
Each group has elements with similar chemical properties
Two major categories are metals and nonmetals
Metalloids have intermediate properties

32. Periodic table Horizontal rows are periods
Physical and chemical properties change across a period
Elements close together have more similar properties than those that are far apart

33. Periodic table
Two sets of elements below the table are the lanthanide and actinide series that fit just after elements 57 and 89
Placed below to prevent the table from being too wide

34. Periodic table: metals
On the left and in the center
Have metallic luster (shininess)
Conduct electricity
Most are solids at room temperature
They are malleable (rolled into sheets)
They are ductile (drawn into wire)
High tensile strength (resist breakage)

35. Periodic table: nonmetals
Many are gases at room temperature, one is liquid, some are solids
They are brittle not ductile or malleable
Low conductivity of heat / electricity

36. Periodic table: noble gases
Group 18
Generally unreactive

37. Periodic table: metalloids
Located between metals and nonmetals
Share some characteristics with metals and some with nonmetals
All are solids at room temperature
Less malleable than metals and not as brittle as nonmetals; some have luster
Some are semiconductors of electricity

38. Compounds Combine 2 or more elements
Ex: water, table salt, table sugar, aspirin
Can be broken down into elements with heat/electricity

39. Law of Definite Proportions
Regardless of the amount, a compound is always made of the same elements in the same proportions by mass
Ex: table sugar = C, H, O
Refer to p. 75 Tables 3-4 and 3-5

40. Law of Multiple Proportions
When different compounds are formed by a combination of the same elements, they combine in whole # ratios
Ex: Cu compounds on p. 76 Table 3-6