CHEMISTRY 1211CHEMISTRY 1211Chapter 1Chapter 1

CHEMISTRYCHEMISTRYWHAT IS IT?WHAT IS IT?

SCIENCE SCIENCE DEALING WITH DEALING WITH

THE THE COMPOSITION COMPOSITION

AND ENERGY OF AND ENERGY OF MATTER AND THE MATTER AND THE

CHANGES IN CHANGES IN COMPOSITION COMPOSITION AND ENERGY AND ENERGY THAT MATTER THAT MATTER UNDERGOES.UNDERGOES.

WHAT IS A WHAT IS A SCIENCE?SCIENCE?

SCIENCESCIENCE

AN ORGANIZED AN ORGANIZED BODY OF BODY OF

KNOWLEDGEKNOWLEDGE

Scientific Method:Scientific Method:

A systematic approach to solving A systematic approach to solving problems.problems.

WHAT IS WHAT IS MATTER?MATTER?

MATTERMATTER

ANYTHING THAT ANYTHING THAT HAS MASS AND HAS MASS AND

OCCUPIES SPACEOCCUPIES SPACE

MatterMatter

Atoms are the building blocks of matter.Atoms are the building blocks of matter. Each element is made of the same kind Each element is made of the same kind

of atom.of atom.

CLASSIFICATIOCLASSIFICATION OF MATTERN OF MATTER

States of MatterStates of Matter

Classification of MatterClassification of Matter

MATTERMATTER

PURE SUBSTANCESPURE SUBSTANCES

OROR

MIXTURESMIXTURES

PURE SUBSTANCESPURE SUBSTANCES

DISTINCT PROPERTIESDISTINCT PROPERTIES CONSTANT CONSTANT

COMPOSITIONCOMPOSITION TWO TYPES:TWO TYPES:

ELEMENTSELEMENTSCOMPOUNDSCOMPOUNDS

PURE SUBSTANCESPURE SUBSTANCES

ELEMENT: SUBSTANCE ELEMENT: SUBSTANCE CONTAINING ONLY ONE CONTAINING ONLY ONE TYPE OF ATOMTYPE OF ATOM

ATOMATOM

THE SMALLEST THE SMALLEST REPRESENTATIVE REPRESENTATIVE PARTICLE OF AN PARTICLE OF AN

ELEMENTELEMENT

PURE SUBSTANCESPURE SUBSTANCES

COMPOUND: SUBSTANCE COMPOUND: SUBSTANCE CONTAINING TWO OR MORE CONTAINING TWO OR MORE TYPES OF ATOMS IN A FIXED TYPES OF ATOMS IN A FIXED RATIO RATIO

MIXTURESMIXTURES

CONTAINS TWO OR MORE CONTAINS TWO OR MORE DIFFERENT SUBSTANCESDIFFERENT SUBSTANCES

TWO TYPESTWO TYPESHETEROGENEOUSHETEROGENEOUSHOMOGENEOUSHOMOGENEOUS

HETEROGENEOUSHETEROGENEOUSSUBSTANCES ARE VISUALLY SUBSTANCES ARE VISUALLY

DISTINGUISHABLEDISTINGUISHABLE

HOMOGENEOUSHOMOGENEOUSSUBSTANCES ARE VISUALLY SUBSTANCES ARE VISUALLY

INDISTINGUISHABLEINDISTINGUISHABLE

PROPERTIES OF MATTERPROPERTIES OF MATTER

PHYSICAL PROPERTIES vs PHYSICAL PROPERTIES vs CHEMICAL PROPERTIESCHEMICAL PROPERTIES

INTENSIVE PROPERTIES INTENSIVE PROPERTIES vs EXTENSIVE vs EXTENSIVE PROPERTIESPROPERTIES

PHYSICAL vs CHEMICAL PHYSICAL vs CHEMICAL PROPERTIESPROPERTIES

PHYSICAL PROPERTIES CAN BE PHYSICAL PROPERTIES CAN BE MEASURED WITHOUT MEASURED WITHOUT CHANGING THE IDENTITY OR CHANGING THE IDENTITY OR COMPOSITIONCOMPOSITION

CHEMICAL PROPERTIES CHEMICAL PROPERTIES DESCRIBE THE WAY A DESCRIBE THE WAY A SUBSTANCE CHANGES OR SUBSTANCE CHANGES OR REACTS TO FORM OTHER REACTS TO FORM OTHER SUBSTANCESSUBSTANCES

INTENSIVE vs EXTENSIVE INTENSIVE vs EXTENSIVE PROPERTIESPROPERTIES

INTENSIVE – NOT DEPENDENT INTENSIVE – NOT DEPENDENT ON THE AMOUNT OF ON THE AMOUNT OF SUBSTANCE PRESENT SUBSTANCE PRESENT (TEMPERATURE, DENSITY, (TEMPERATURE, DENSITY, COLOR, MELTING POINT, COLOR, MELTING POINT, BOILING POINT, ETC.)BOILING POINT, ETC.)

EXTENSIVE – DEPENDS ON EXTENSIVE – DEPENDS ON AMOUNT OF SUBSTANCE AMOUNT OF SUBSTANCE PRESENT (MASS AND VOLUME)PRESENT (MASS AND VOLUME)

UNITS OF UNITS OF MEASUREMENTMEASUREMENTTHE SI SYSTEMTHE SI SYSTEM

LENGTHLENGTH - METER (m)- METER (m) VOLUMEVOLUME - LITER (L)- LITER (L) TIMETIME - SECOND (s)- SECOND (s) MASSMASS - KILOGRAM - KILOGRAM

(kg)(kg) TEMPERATURETEMPERATURE- KELVIN (K)- KELVIN (K)

TEMPERATURETEMPERATURE

K = K = ooC + 273.15C + 273.15

ANDANDooC = 5/9 (C = 5/9 (ooF - 32)F - 32)

OR OR ooF = 9/5 (F = 9/5 (ooC) + 32C) + 32

SIGNIFICANT SIGNIFICANT FIGURESFIGURES

akaaka

SIG FIGSSIG FIGS

akaaka

SFSF

SIGNIFICANT FIGURESSIGNIFICANT FIGURES

IN COUNTING AND DEFINITIONS, IN COUNTING AND DEFINITIONS, THERE ARE AN INFINITE NUMBER THERE ARE AN INFINITE NUMBER OF SIG FIGSOF SIG FIGS

IN MEASUREMENTS, THE NUMBER IN MEASUREMENTS, THE NUMBER OF SIG FIGS CONSISTS OF ALL OF SIG FIGS CONSISTS OF ALL CERTAIN AND THE FIRST CERTAIN AND THE FIRST UNCERTAIN DIGITSUNCERTAIN DIGITS

RULES FOR READING/RECORDING RULES FOR READING/RECORDING MEASURED VALUESMEASURED VALUES

LEADING ZEROS ARE NEVER LEADING ZEROS ARE NEVER SIGNIFICANTSIGNIFICANT

CAPTIVE ZEROS ARE ALWAYS CAPTIVE ZEROS ARE ALWAYS SIGNIFICANTSIGNIFICANT

TRAILING ZEROS ARE TRAILING ZEROS ARE SIGNIFICANT SIGNIFICANT ONLYONLY IF A IF A DECIMAL IS PRESENTDECIMAL IS PRESENT

ROUNDING RULESROUNDING RULES

LOOK ONLY AT NUMBER LOOK ONLY AT NUMBER JUST TO RIGHT OF NUMBER JUST TO RIGHT OF NUMBER YOU ARE ROUNDING TO:YOU ARE ROUNDING TO:IF 5 OR MORE, ROUND UPIF 5 OR MORE, ROUND UPIF LESS THAN 5, ROUND IF LESS THAN 5, ROUND DOWNDOWN

MATH OPERATIONS INVOLVING MATH OPERATIONS INVOLVING SIGNIFICANT FIGURESSIGNIFICANT FIGURES

MULTIPLICATION / DIVISION: MULTIPLICATION / DIVISION: ANSWER WILL HAVE SAME TOTAL # ANSWER WILL HAVE SAME TOTAL # OF SIG FIGS AS THE NUMBER WITH OF SIG FIGS AS THE NUMBER WITH THE LEAST TOTAL # OF SIG FIGSTHE LEAST TOTAL # OF SIG FIGS

ADDITION / SUBTRACTION: ANSWER ADDITION / SUBTRACTION: ANSWER HAS SAME # OF DIGITS AFTER HAS SAME # OF DIGITS AFTER DECIMAL AS THE NUMBER WITH THE DECIMAL AS THE NUMBER WITH THE LEAST # OF DIGITS AFTER THE LEAST # OF DIGITS AFTER THE DECIMALDECIMAL

GENERAL RULEGENERAL RULE

CARRY ALL FIGURES CARRY ALL FIGURES THROUGH TO THE END THROUGH TO THE END OF A PROBLEM. ROUND OF A PROBLEM. ROUND THE FINAL ANSWER TO THE FINAL ANSWER TO THE CORRECT NUMBER THE CORRECT NUMBER

OF SIGNIFICANT OF SIGNIFICANT FIGURES.FIGURES.

Accuracy versus Accuracy versus PrecisionPrecision

AccuracyAccuracy refers to the refers to the proximity of a measurement to proximity of a measurement to the true value of a quantity.the true value of a quantity.

PrecisionPrecision refers to the refers to the proximity of several proximity of several measurements to each other.measurements to each other.

DENSITYDENSITY

DENSITY IS AN DENSITY IS AN INTENSIVE INTENSIVE

PROPERTY OF PROPERTY OF MATTER. MATTER.

THEREFORE, THEREFORE, DENSITY IS DENSITY IS

INDEPENDENT OF INDEPENDENT OF HOW MUCH SAMPLE HOW MUCH SAMPLE

IS PRESENTIS PRESENT

DENSITYDENSITY

DENSITY IS DEFINED AS THE DENSITY IS DEFINED AS THE MASS PER UNIT VOLUME OF A MASS PER UNIT VOLUME OF A

SUBSTANCESUBSTANCE

D = m/VD = m/V

USUALLY IN UNITS OF:USUALLY IN UNITS OF:

g/mL or g/cmg/mL or g/cm33