Matter and Energy

Preparation of College ChemistryColumbia UniversityDepartment of Chemistry

Classification of Matter

State

Composition

Four states of Matter

Solid

Liquid

Gas

Plasma

Composition of Matter

Elements

Compounds

Mixtures

Matter Classification

Matter

Mixtures Pure Substances

HeterogeneousMore than one phase

HomogeneousOne Phase(Solutions)

Elements Compounds

SystemOrgan Tissue

Macromolecule

CellOrganelle

Protons

Neutrons

Atom (Elements)

Levels of Organization

Organism

Object

Leptons

Quarks,... http://www.bnl.gov/RHIC/

Molecule

Electrons

Average Elemental Composition of Human Body

1.0Traces of other elements

1.0Phosphorus

2.0Calcium

3.0Nitrogen

10.0Hydrogen

18.0Carbon

65.0Oxygen

Mass %Element

Elements’ Distribution (earth, sea, atmosphere)

0.47All others0.58Titanium

0.87Hydrogen

0.03Fluorine1.93Magnesium

0.03Nitrogen2.40Potassium

0.04Barium2.63Sodium

0.06Sulfur3.39Calcium

0.08Carbon4.71Iron

0.09Manganese7.50Aluminum

0.11Phosphorus25.67Silicon

0.19Chlorine49.20Oxygen

Mass %ElementMass %Element

Metalloids

Ag

Na

Li

Fr

Cs

Rb

K

Be

Ca

Mg

Ra

Ba

Sr

Sc

La

Y

Ac

Ti

Hf

Zr

Rf

V

Ta

Nb

Ha

Cr

W

Mo

Sg

Mn

Re

Tc

Bh

Fe

Os

Ru

Hs

Co

Ir

Rh

Mt

Ni

Pt

Pd

Cu

Au

Zn

Hg

Cd

Ga

Al

Tl

In

Pb

Sn

Bi Po

B

Ge

Si

As

Sb Te

At

H

C N

P

O

Se

S

F

Br

Cl

I

Ne

Kr

Ar

Rn

Xe

He

Ce

Th

Pr

Pa

Nd

U

Pm

Np

Sm

Pu

Eu

Am

Gd

Cm

Tb

Bk

Dy

Cf

Ho

Es

Er

Fm

Tmi

Md

Yb

No

Lu

Lr

Inner-Transition Metals

Transition Metals

Main-Group Elements Main-Group Elements

Lantanides

Actinides

Metals, Nonmetals,

47

11

3

87

55

37

19

4

20

12

88

56

38

21

57

39

89

22

72

40

104

23

73

41

105

24

74

42

106

25

75

43

107

26

76

44

108

27

77

45

109

28

78

46

29

79

30

80

48

31

13

8l

49

82

50

83 84

5

32

14

33

51 52

85

1

6 7

15

8

34

16

9

35

17

53

10

36

18

86

54

2

58

90

59

91

60

92

61

93

62

94

63

95

64

96

65

97

66

98

67

99

68

100

69

101

70

102

71

103

Ag

Na

Li

Fr

Cs

Rb

K

Be

Ca

Mg

Ra

Ba

Sr

Sc

La

Y

Ac

Ti

Hf

Zr

Rf

V

Ta

Nb

Ha

Cr

W

Mo

Sg

Mn

Re

Tc

Bh

Fe

Os

Ru

Hs

Co

Ir

Rh

Mt

Ni

Pt

Pd

Cu

Au

Zn

Hg

Cd

Ga

Al

Tl

In

Pb

Sn

Bi Po

B

Ge

Si

As

Sb Te

At

H

C N

P

O

Se

S

F

Br

Cl

I

Ne

Kr

Ar

Rn

Xe

He

Ce

Th

Pr

Pa

Nd

U

Pm

Np

Sm

Pu

Eu

Am

Gd

Cm

Tb

Bk

Dy

Cf

Ho

Es

Er

Fm

Tmi

Md

Yb

No

Lu

Lr

8A Noble Gases

Ga

Al

Tl

In

B

Pb

Sn

Ge

Si

C N

Bi

As

Sb

P

Po

Te

O

Se

SBr

I

At

F

Cl

Ne

Kr

Ar

Rn

Xe

He

7A Halogens

6A Chalcogens5A4A3A

1A Alkali metals

2A Alkaline earth metals

Na

Rb

K

Fr

Cs

Li

Mg

Sr

Ca

Ra

Ba

Be

Elements that Exist as Diatomic Molecules

Bluish-black solidI2IIodine

Reddish-brown liquidBr2BrBromine

Yellow-green gasCl2ClChlorine

Pale yellow gasF2FFluorine

Colorless gasO2OOxygen

Colorless gasN2NNitrogen

Colorless gasH2HHydrogen

Normal StateMolecular FormulaSymbolElement

Allotropic Forms (Allotropes) Berzelius, 1841

CarbonGraphite

Diamond

Nanotubes

Buckyballs (C60 )

OxygenOxygen (O2 )

Ozone (O3 )

Oxygen Singlet (O2* )

Allotropic Forms (Allotropes)

Sulfur

Monoclinic (S8 )

Amorphous (Sn )

Rhombic (S8 )

Phosphorus

White phosphorus, (P4 ), d =1.82

Red phosphorus, (Pn ), d = 2.20

Violet phosphorus, (Pn ), d = 2.32

Black phosphorus, (Pn ), d = 2.70

Compounds

Contain two or more elements with fixed mass percents

Sodium chloride: 39.34% Na60.66% Cl

Glucose: 40.00% C6.71% H53.29% O

Covalent:

Ionic:

Depending Upon Bonding Type

Compounds

Ionic (Coulombic forces)

Molecular(Covalent bonds)

MoleculesCations Anions

Properties of Substances

Intensive vs. Extensive: density vs. mass

Chemical vs. Physical

Chemical vs. Physical Properties

Chemical Properties

Physical Properties

Molecules or ions undergo a change instructure or composition

Can be studied without a change instructure or composition

Properties of Substances

Intensive vs. Extensive: density vs. mass

Chemical vs. Physical

Extensive Properties

Vary with the amount of material

• Mass

• Volume

• Internal Energy

• Enthalpy

• Entropy

Intensive Properties

Independent of the amount of material

Density (mass per unit volume)

Temperature (average energy per particle)

Energy

Heat: Quantitative Measurement

Energy in Chemical Changes

Radiant (light)

Thermal (heat)

Chemical

Electrical

Mechanical

In any chemical or physical change, energy can be convertedfrom one form to another, but it is neither created nor destroyed

Law of Conservation of Energy:

Is the energy available but not being used or is it in use?

Forms of Energy Types of Energy

Kinetic Energy (Motion Energy)

Energy(Capacity to do work)

Potential Energy (Stored Energy)

o Position,o Compositiono Condition

†

Ek =12

mv2

Heat Energy and Specific HeatUnits of Energy:

Amount of kinetic energy possessed by a 2kg object moving at a speed of1m/s. Substituting these values in the equation that defines kinetic energy:

Joule :

Equivalent to the amount of energy you willfeel if you drop 4.4 lb from about 4 in. onto your foot.

calorie (cal) :

Amount of heat energy needed to raise the temperature of one gram ofwater by one degree Celsius measured between 14.5 and 15.5°C.

†

Ek =12

mv2

†

Joule =kgm2

s2

1kcal = 4.3184kJ1C = 1kcal = 103 cal

Sprite™ contains 140 C:

1 BTU (British Thermal Unit):

140,000 cal of energy is released when thesoft drink is metabolized within the body.

Amount of heat needed to raise thetemperature of a lb of water one °F

1 cal = 4.3184 J

The joule and calorie are rather small units.

The large calorie (Cal, C) is used to express the energycontent of foods.

Units of Energy

1BTU =.818 kcal

Specific HeatAmount of heat needed to raise the temperature of 1 g ofa substance in a specific physical state by 1°C

Units: cal /g °C or J/g °C

“Amount of heat needed to raise the temperature of asubstance by the same amount depends on the substance”

Amount of heat needed to raise the temperature of agiven quantity of substance in a specific physical state.

Joseph Black (~1750):

Heat Capacity and Specific Heat

Heat Capacity

The specific heat of a substance changes when thephysical state of the substance changes

2 .1 J / g °C 2 . 0 J / g °C 4 . 18 J / g °C

The higher the specific heat of a substance, the less itstemperature will change when it absorbs a given amount of heat.

At the beach, sand has a lower specific heat thanwater, so it heats up while water stays cool.

metals heat up quickly, but cool quickly

Water (ice) Water (steam) Water (liquid)Ex.

Solving problemsHeat transferred = mass x Specific heat x ∆T

q = m x Cs x ∆T

1. Amount of heat energy needed to cause a fixed amount of a substanceto undergo a specific temperature change without causing a change ofstate.

2. Transfer of heat from one body to another.

I. Heat always flows from the warmer body tothe colder body.

II. The heat loss by the warmer body is equal tothe heat gained by the colder body.

Generalizations:

Heat in Chemical Change

Potential Energy Diagrams

H2O

Electrolysis Direct synthesis

H2 O2+

H2O

time

Pot

entia

l ene

rgy

Pot

entia

l ene

rgy

time

H2 O2+