CHEMISTRY BOOTCAMP #1

MATTER* is anything that has mass and takes up space

Two things to consider when looking at different types of MATTER

TWO Types of MATTER

• PURE SUBSTANCE – Type of matter with a uniform and fixed composition

• MIXTURE – Two or more pure substances that have been physically combined and have a variable composition

TWO Types of PURE SUBSTANCES

• ELEMENT – pure substance that cannot be decomposed (broken down) by a chemical change

• COMPOUND – 2 or more elements that are chemically combined in a fixed proportion AND can be decomposed by a chemical change

Two Types of MIXTURES

• Homogeneous mixture – all parts are evenly distributed and look the same throughout

– Aqueous (aq) – mixed with water & is homogeneous

• Heterogeneous mixture – parts are not evenly distributed and look different throughout

Two Types of Matter

SEPARATING MIXTURES • Homogeneous mixtures require EVAPORATION

(CRYSTALLIZATION) because the solids are fully dissolved in the liquid – Ex: SALT WATER

– Salt is fully dissolved and mixture looks same throughout

• Heterogeneous mixtures require FILTRATION because the solids are large enough to be caught in a filter – Ex: SAND AND WATER

– You can see the sand and it does not dissolve in water

States of Matter

Yes No No

Yes Yes No

(s)

Ex: NaCl(s), CCl4(s)

(l)

Ex: H2O(l), Hg(l) (g)

Ex: O2(g), CO2(g)

Standard Temperature and Pressure (STP)

STP = Standard Temperature and Pressure Find on Table A. Standard Temperature: ____101.3 kPa____ Standard Pressure: ______273 K________

A substance has a melting point of 230 K and a boiling point of 769 K. What state of matter is this substance in at:

a) 300 K b) 100 K c) 1000 K d) 500 K e) STP

Property: a characteristic of a substance that can be observed

Physical Properties

Physical property: a property that can be observed without changing the identity of the substance

Examples:

• color

• odor

• luster

• malleability: the ability to be hammered into a thin sheet

• ductility: the ability to be stretched into a wire

• melting point

• boiling point

• conductivity

• solubility

• density

Chemical Properties

• Chemical property: a property that can only be observed by changing the identity of the substance

Examples:

•flammability

•ability to rust

•reactivity with vinegar

How do you know if it is chemical or physical? - If it CHanges, it’s CHemical

DENSITY is an important physical property. • Density - The amount of

“stuff” or particles (mass) in a given volume of space.

• Density is the mass of an object measured in grams, divided by the volume of an object measured in mL or cm3. The standard unit for density is g/cm3.

Example Problem: If an object has a mass of 3.0 grams and has a volume of 2 mL (2 cm3), what is the density of the object? Density= = = 1.5 g/mL or 1.5 g/cm3

Remember our density lab?

Physical Changes

• Changes that do NOT change the identity of the substance.

• You may or may not be able to undo a physical change.

Chemical Changes • Changes that do change the identity of a substance

• In other words, a chemical change is when something

changes into an entirely different substance

• For example: – Iron rusting – Wood burning – Copper turning to brass – Baking a cake – spoiled milk

The periodic table is organized by properties

– Elements with similar properties occupy the same general area of the periodic table

Metals and Nonmetals

Li

3

He

2

C

6

N

7

O

8

F

9

Ne

10

Na

11

B

5

Be

4

H

1

Al

13

Si

14

P

15

S

16

Cl

17

Ar

18

K

19

Ca

20

Sc

21

Ti

22

V

23

Cr

24

Mn

25

Fe

26

Co

27

Ni

28

Cu

29

Zn

30

Ga

31

Ge

32

As

33

Se

34

Br

35

Kr

36

Rb

37

Sr

38

Y

39

Zr

40

Nb

41

Mo

42

Tc

43

Ru

44

Rh

45

Pd

46

Ag

47

Cd

48

In

49

Sn

50

Sb

51

Te

52

I

53

Xe

54

Cs

55

Ba

56

Hf

72

Ta

73

W

74

Re

75

Os

76

Ir

77

Pt

78

Au

79

Hg

80

Tl

81

Pb

82

Bi

83

Po

84

At

85

Rn

86

Fr

87

Ra

88

Rf

104

Db

105

Sg

106

Bh

107

Hs

108

Mt

109

Mg

12

Ce

58

Pr

59

Nd

60

Pm

61

Sm

62

Eu

63

Gd

64

Tb

65

Dy

66

Ho

67

Er

68

Tm

69

Yb

70

Lu

71

Th

90

Pa

91

U

92

Np

93

Pu

94

Am

95

Cm

96

Bk

97

Cf

98

Es

99

Fm

100

Md

101

No

102

Lr

103

La

57

Ac

89

1

2

3

4

5

6

7

METALS

Nonmetals

Metalloids

Nonmetals Metalloids Metals

plum-pudding rutherford bohr wave-mechanical

History of the Atom

Rutherford’s Nuclear Model: • Atom is mostly empty space • Dense, positively-charged nucleus (protons + neutrons) • Negatively-charged electron cloud surrounding the nucleus

The Atom

Key Points: • Atomic number – identifies an element & is the number of protons • Charge of atom is neutral – # of protons equals # of electrons • Charge of nucleus is positive – protons + neutrons = positive

Isotope – an atom of an element with a different number of neutrons

• All isotopes have different

masses • To get the mass of an isotope,

you add the # of protons and the # of neutrons

• Mass number - identifies an isotope - # of protons + # of neutrons

Calculating Average Atomic Mass • Boron exists as two isotopes: Boron-10 and Boron-11

• Boron-10 has a mass of 10.01 amu and makes up 19.9% of all boron that exists

• Boron-11 has a mass of 11.01 amu and makes up 80.1% of all boron that exists

• To calculate the average atomic mass of boron, multiply the mass of each boron isotope by its percent abundance