1 matter matter: anything that occupies space and has mass

11

MatterMatterMatterMatter: Anything that occupies space and has mass.: Anything that occupies space and has mass.

22

Physical PropertiesPhysical PropertiesPhysical PropertiesPhysical Properties: They can be measured and observed without : They can be measured and observed without

changing the composition or identity of a substance.changing the composition or identity of a substance.

ExamplesExamplesOdor, Color, Volume, Matter, Density, Melting Point, Boiling Odor, Color, Volume, Matter, Density, Melting Point, Boiling

PointPoint

33

A Further Breakdown: Extensive A Further Breakdown: Extensive vs. Intensive Physical Propertiesvs. Intensive Physical Properties

Extensive Properties: depend on amt of substance (mass, Extensive Properties: depend on amt of substance (mass, volume)volume)

Intensive Properties: do NOT depend on amt of substance Intensive Properties: do NOT depend on amt of substance (melting point, boiling point)(melting point, boiling point)

44

Chemical PropertiesChemical Properties Properties in which there is a change in compositionProperties in which there is a change in composition Reactivity, flammability, etc.Reactivity, flammability, etc. Subdivided into physical and chemical changesSubdivided into physical and chemical changes

55

Physical Physical ChangesChanges

Physical ChangePhysical Change: change in physical properties: change in physical properties

ExamplesExamples

Ice melting, water boilingIce melting, water boiling

66

Chemical Chemical ChangesChanges

Chemical ChangesChemical Changes: Forming new substance(s): Forming new substance(s)

ExamplesExamples

Rusting of nails, digestion of food in our stomach, the growth of Rusting of nails, digestion of food in our stomach, the growth of grassgrass

77

PracticePracticeClassify the following as a physical or chemical change or physical or chemical Classify the following as a physical or chemical change or physical or chemical

property:property:

(a) Gallium metal melts in your hand (and in your mouth).(a) Gallium metal melts in your hand (and in your mouth).

(b) A Page is White.(b) A Page is White.

(c) Copper sheet acquires a green color over the years.(c) Copper sheet acquires a green color over the years.

(d) Milk turns sour.(d) Milk turns sour.

(e) Wax is melted over a flame.(e) Wax is melted over a flame.

(f) Propane gas is flammable.(f) Propane gas is flammable.

(g) Bromine liquid is reddish-brown in color.(g) Bromine liquid is reddish-brown in color.

88

Pure Substances: Pure Substances: Elements and CompoundsElements and Compounds

ElementElement: A substance that cannot be separated into simpler : A substance that cannot be separated into simpler substances by chemical means.substances by chemical means.

ExampleExampleGold and…?Gold and…?

CompoundCompound: A substance composed of atoms of 2 or more : A substance composed of atoms of 2 or more elements chemically united in fixed proportions.elements chemically united in fixed proportions.

ExampleExampleSodium Chloride and…?Sodium Chloride and…?

99

MixturesMixturesMixtureMixture: A combination of 2 or more substances in which the : A combination of 2 or more substances in which the substances retain their identity though no longer seen.substances retain their identity though no longer seen.

ExamplesExamplesAir, Soft Drinks, Wine, Coffee, Water pumped from the Earth.Air, Soft Drinks, Wine, Coffee, Water pumped from the Earth.Can you think of anymore…?Can you think of anymore…?

They can be separated into pure substances: They can be separated into pure substances: Elements and/or Compounds. Elements and/or Compounds.

They can converted into two or more pure substances.They can converted into two or more pure substances.

1010

MixturesMixtures Homogeneous MixtureHomogeneous Mixture: The composition of the mixture, after : The composition of the mixture, after

sufficient stirring, is the same throughout the solution. A sufficient stirring, is the same throughout the solution. A homogeneous mixture is called a homogeneous mixture is called a solutionsolution. It has one layer.. It has one layer. Ex: Salt dissolved in water.Ex: Salt dissolved in water.

Heterogeneous MixtureHeterogeneous Mixture: The individual components of a : The individual components of a mixture remain physically separated and can be seen as mixture remain physically separated and can be seen as separate components. It has more than one layer.separate components. It has more than one layer.

Ex: A glass full of oil and water or sand in a bucket of water.Ex: A glass full of oil and water or sand in a bucket of water.

1111

PracticePracticeClassify the following as a pure substance, a homogeneous Classify the following as a pure substance, a homogeneous

mixture (solution) or a heterogeneous mixture:mixture (solution) or a heterogeneous mixture:

(a) Soda(a) Soda

(b) Kool-Aid(b) Kool-Aid

(c) Oil and Vinegar(c) Oil and Vinegar

(d) Common Table Salt (Sodium Chloride)(d) Common Table Salt (Sodium Chloride)

(e) A vein of gold embedded in quartz(e) A vein of gold embedded in quartz

1212

Separation of MixturesSeparation of MixturesDistillationDistillation: is the process of vaporizing a liquid in a boiling pot : is the process of vaporizing a liquid in a boiling pot

and then condensing (gas and then condensing (gas liquid) it again where it will liquid) it again where it will collect in another vessel. collect in another vessel.

Used to separate water from dissolved materials (solid or Used to separate water from dissolved materials (solid or liquid)liquid)

Used to make moon-shine; i.e., separate ethanol from Used to make moon-shine; i.e., separate ethanol from impuritiesimpurities

1313

Simple DistillationSimple Distillation

1414

Separation of MixturesSeparation of MixturesFiltrationFiltration: the process of causing a liquid-solid heterogeneous : the process of causing a liquid-solid heterogeneous

mixture to encounter a porous barrier so that the liquid passes mixture to encounter a porous barrier so that the liquid passes through. The solid is left behind. through. The solid is left behind.

The liquid that passes through is called the The liquid that passes through is called the filtratefiltrate. . The remaining solid is the residue, or The remaining solid is the residue, or filter cakefilter cake..

There are two purposes for filtrations:There are two purposes for filtrations:

(1) to remove solid impurities from a liquid.(1) to remove solid impurities from a liquid.

(2) to separate solid products from a liquid.(2) to separate solid products from a liquid.

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Scientific NotationScientific NotationHandling Numbers Associated with MeasurementsHandling Numbers Associated with Measurements

Scientific NotationScientific Notation: Expresses a number as a product of a number : Expresses a number as a product of a number between 1 and 10 and the appropriate power of 10.between 1 and 10 and the appropriate power of 10.

These numbers are very large and very small. They are These numbers are very large and very small. They are cumbersomecumbersome

Example:Example: 702,400,000,000,000,000,000 702,400,000,000,000,000,000 0.00000000000000000000768 0.00000000000000000000768

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Using Scientific NotationUsing Scientific Notation1.1. Any number can be represented as the product of a number Any number can be represented as the product of a number

between 1 and 10 and a power of 10 (either positive or between 1 and 10 and a power of 10 (either positive or negative).negative).

2.2. The decimal point should be placed with a one non-zero The decimal point should be placed with a one non-zero number to its left. number to its left.

3.3. The power of 10 depends on the number of places the The power of 10 depends on the number of places the decimal point is moved and in which direction.decimal point is moved and in which direction.

4.4. If the decimal point is moved to the left, the power of 10 is If the decimal point is moved to the left, the power of 10 is positive. If the decimal point is moved to the right, the positive. If the decimal point is moved to the right, the power of 10 is negative.power of 10 is negative.

1717

ExamplesExamples Express 685,000 in scientific notation:Express 685,000 in scientific notation:

The decimal point must be moved The decimal point must be moved fivefive places to the left places to the left Thus, the decimal point has one non-zero number to its leftThus, the decimal point has one non-zero number to its left 6.85 x 106.85 x 1055

Express 0.00000663 in scientific notation:Express 0.00000663 in scientific notation: The decimal point must be moved The decimal point must be moved sixsix places to the right places to the right Thus, the decimal point has one non-zero number to its leftThus, the decimal point has one non-zero number to its left 6.63 x 106.63 x 10-6-6

Try these: Try these: 809,000,000,000809,000,000,000 0.00000000060.0000000006

1818

Fundamental SI UnitsFundamental SI UnitsUnitsUnits: The units part of a measurement tells us what quantity is : The units part of a measurement tells us what quantity is

being used to represent the results of the measurement.being used to represent the results of the measurement. SI = Systeme Internationale (French)SI = Systeme Internationale (French)

Physical QuantityPhysical Quantity Name of UnitName of Unit AbbreviationAbbreviation

mass kilogram kgmass kilogram kg

length meter mlength meter m

time second stime second s

temperature kelvin Ktemperature kelvin K

amount of substance mole molamount of substance mole mol

1919

Measurements of Measurements of Length, Volume, and MassLength, Volume, and Mass

LengthLength: Measurement of how long a thing is from end to end.: Measurement of how long a thing is from end to end. The SI base unit of length is the meter (m).The SI base unit of length is the meter (m).

VolumeVolume: Amount of 3-D space occupied by a substance.: Amount of 3-D space occupied by a substance. Its SI derived unit is mIts SI derived unit is m33.. Another common unit of volume is the liter (l).Another common unit of volume is the liter (l).

MassMass: Quantity of matter present in an object. : Quantity of matter present in an object. The SI base unit of mass is the kilogram (kg).The SI base unit of mass is the kilogram (kg).

Prefixes can be used for all units:Prefixes can be used for all units: i.e., milligram, milliliter, millimeteri.e., milligram, milliliter, millimeter

2020

Prefixes used with SI UnitsPrefixes used with SI UnitsPrefixPrefix SymbolSymbol MeaningMeaning Tera T 1 x 10Tera T 1 x 101212

Giga G 10Giga G 1099

Mega M 10Mega M 1066

Kilo k 10Kilo k 1033

DecaDeca D D 10 1011

deci d 10deci d 10-1-1

centi c 10centi c 10-2-2

milli m 10milli m 10-3-3

micro micro 10 10-6-6

nano n 10nano n 10-9-9

pico p 10pico p 10-12-12

2121

The Use of PrefixesThe Use of Prefixes 1 dL = 1 x 101 dL = 1 x 10-1-1 L = 0.1 L L = 0.1 L

1 mg = 1 x 101 mg = 1 x 10-3-3 g = 0.001 g g = 0.001 g 1 km = 1 x 101 km = 1 x 1033 m = 1000 m m = 1000 m

2222

Uncertainty in MeasurementUncertainty in MeasurementMeasurementsMeasurements

3.00 cm 3.01 cm 3.02 cm 3.00 cm 3.01 cm 3.02 cm

Notice that the first two digits are the same. Notice that the first two digits are the same. These are called the These are called the certain numberscertain numbers. . The third digit is estimated and can vary. The third digit is estimated and can vary. It is called an It is called an uncertain numberuncertain number. . Give the certain and uncertain numbers in the following Give the certain and uncertain numbers in the following

measurements:measurements: 2.509 kg2.509 kg 1.0596 L1.0596 L

2323

Precision & AccuracyPrecision & Accuracy

Precision: Precision: How well measurements agree with How well measurements agree with one anotherone another

Accuracy: Accuracy: agreement of measurement with agreement of measurement with accepted (book) valueaccepted (book) value

2424

PracticePractice

A 5-page package of high quality printing A 5-page package of high quality printing paper had its length measured in inches. The paper had its length measured in inches. The measurements obtained were:measurements obtained were:

11.003, 11.003, 11.004, 11.003, 11.00311.003, 11.003, 11.004, 11.003, 11.003 The cover says its length is 11.003 inches.The cover says its length is 11.003 inches. Do you have “good” or “bad” precision?Do you have “good” or “bad” precision? What about your accuracy: “good” or “bad”?What about your accuracy: “good” or “bad”?

2525

More Practice More Practice

Five blank writable CD’s had the same piece Five blank writable CD’s had the same piece of music burned on to them. The original CD of music burned on to them. The original CD said that the track was two minutes and thirty-said that the track was two minutes and thirty-three seconds (2’33”) long. three seconds (2’33”) long.

However, the length of the track on the burned However, the length of the track on the burned CD’s was the following:CD’s was the following:2’15”, 2’15”, 2’15”, 2’15”, 2’15”2’15”, 2’15”, 2’15”, 2’15”, 2’15”

Do you have “good” or “bad” precision?Do you have “good” or “bad” precision? What about your accuracy: “good” or “bad”?What about your accuracy: “good” or “bad”?

2626

Significant FiguresSignificant FiguresSignificant FiguresSignificant Figures: Numbers recorded in a : Numbers recorded in a

measurement.measurement. (All the certain numbers+the first uncertain (All the certain numbers+the first uncertain

number)number)

The more significant figures (sig figs) in a The more significant figures (sig figs) in a measurement the greater the precision.measurement the greater the precision. 32.0 is less precise than 32.00000032.0 is less precise than 32.000000

2727

Guidelines for Using Guidelines for Using Significant FiguresSignificant Figures

Nonzero IntegersNonzero Integers:: Any digit that is not zero is significant.Any digit that is not zero is significant.

ExampleExample

894 has _________ significant figures.894 has _________ significant figures.

2.341 has _________ significant figures.2.341 has _________ significant figures.

2828


Leading ZerosLeading Zeros:: Zeros to the left of the first nonzero digit are not Zeros to the left of the first nonzero digit are not

significant.significant. They are used to indicate the placement of the They are used to indicate the placement of the

decimal point. decimal point.

ExampleExample

0.07 has __________ significant figures.0.07 has __________ significant figures.


2929


Captive ZerosCaptive Zeros:: Zeros between nonzero digits are significant.Zeros between nonzero digits are significant.

ExampleExample

707 has ___________ significant figures.707 has ___________ significant figures.

50,001 has __________ significant figures.50,001 has __________ significant figures.

3030


Trailing ZerosTrailing Zeros:: If a number is greater than 1, then all the zeros written to If a number is greater than 1, then all the zeros written to

the right of the decimal point count as significant figures.the right of the decimal point count as significant figures.

ExampleExample





8,500 has __________ significant figures.8,500 has __________ significant figures.

3131


Leading, Captive, and Trailing ZerosLeading, Captive, and Trailing Zeros:: If a number is less than 1, then only the zeros that are at If a number is less than 1, then only the zeros that are at

the end of the number, and zeros that are between the end of the number, and zeros that are between nonzero digits are significant.nonzero digits are significant.

ExampleExample 0.070 has ___________ significant figures.0.070 has ___________ significant figures. 0.4006 has ___________ significant figures.0.4006 has ___________ significant figures. 0.00520 has __________ significant figures.0.00520 has __________ significant figures. 0.0006700 has __________ significant figures.0.0006700 has __________ significant figures.

3232


Exact NumbersExact Numbers:: They are assumed to have an unlimited number of They are assumed to have an unlimited number of

significant figures.significant figures.

3333


Numbers With Trailing Zeroes And No Decimal Point:Numbers With Trailing Zeroes And No Decimal Point: For numbers that do not contain decimal points, the measurement is For numbers that do not contain decimal points, the measurement is

said to be said to be ambiguousambiguous..

ExampleExample

700: 1, 2, or 3 sig figs?700: 1, 2, or 3 sig figs?Use Scientific Notation: 7x10Use Scientific Notation: 7x1022 has one sig fig. has one sig fig.7.0x107.0x1022 has two sig figs. has two sig figs.

7.00 x 107.00 x 102 2 has three sig figs.has three sig figs.

(How many significant figures are in 701? Do you need a (How many significant figures are in 701? Do you need a decimal pt?)decimal pt?)

3434

Rounding Off Numbers:Rounding Off Numbers:Rules for Rounding OffRules for Rounding Off

*We like to reduce our number to fewer digits.**We like to reduce our number to fewer digits.*

1. If the digit to be removed is less than 5, then the preceding 1. If the digit to be removed is less than 5, then the preceding digit stays the same. When rounding off, digit stays the same. When rounding off, use only the first use only the first number to the right of the last significant figurenumber to the right of the last significant figure. Do not . Do not round off sequentially.round off sequentially.

ExampleExample 8.934 rounds off to _________ if we only want 2 sig. figs.8.934 rounds off to _________ if we only want 2 sig. figs.

3535

Rounding Off NumbersRounding Off NumbersRules for Rounding OffRules for Rounding Off

2. If the digit to be removed is equal to or greater than 5, then the 2. If the digit to be removed is equal to or greater than 5, then the preceding digit is increased by 1. When rounding off, preceding digit is increased by 1. When rounding off, use use only the first number to the right of the last significant only the first number to the right of the last significant figurefigure. Do not round off sequentially.. Do not round off sequentially.

ExampleExample 8.627 rounds off to ________ if we only want 3 sig. figs.8.627 rounds off to ________ if we only want 3 sig. figs. 0.425 rounds off to ________ if we only want 2 sig. figs.0.425 rounds off to ________ if we only want 2 sig. figs.

3636

Rules for Using Significant Rules for Using Significant Figures in CalculationsFigures in Calculations

Addition and Subtraction:Addition and Subtraction: In the answer, the number of sig figs to the right of the decimal point In the answer, the number of sig figs to the right of the decimal point

are determined by the lowest number of sig figs to the right of the are determined by the lowest number of sig figs to the right of the decimal point given by the measurements.decimal point given by the measurements.

The measurement is said to be limiting. It limits the number of The measurement is said to be limiting. It limits the number of significant figures in the result.significant figures in the result.

ExampleExample90.442 + 1.1 = 90.442 + 1.1 = 91.54291.542 Rounded Off to Rounded Off to 91.591.53.000 - 0.10 = _________ Rounded Off to __________3.000 - 0.10 = _________ Rounded Off to __________1081 - 7.25 = _________1081 - 7.25 = _________

*For Addition and Subtraction, the decimal points are *For Addition and Subtraction, the decimal points are counted as sig figs.*counted as sig figs.*

3737


Multiplication and Division:Multiplication and Division: The number of sig figs is determined by the original The number of sig figs is determined by the original

number that has the smallest number of sig figs. number that has the smallest number of sig figs. The measurement is said to be limiting. It limits the The measurement is said to be limiting. It limits the

number of sig figs in the result.number of sig figs in the result.

ExampleExample(2.7)x(3.5029) = (2.7)x(3.5029) = 9.457839.45783 Rounded Off to Rounded Off to 9.59.5(7.85)/(124.6) = _____ Rounded Off to ____________(7.85)/(124.6) = _____ Rounded Off to ____________*For Multiplication and Division, the whole *For Multiplication and Division, the whole

measurements’ sig figs are counted.*measurements’ sig figs are counted.*

3838


What about:What about:

Order of operations!Order of operations! Follow the add/sub sig figs for each operationFollow the add/sub sig figs for each operation Then divide, following division sig fig rulesThen divide, following division sig fig rules Thus, 7.85 + 11.1 = 19.0Thus, 7.85 + 11.1 = 19.0 And 124.6 – 4 = 121And 124.6 – 4 = 121 Therefore, 19.0/121 = Therefore, 19.0/121 = 0.1570.157

(7.85 + 11.1) = ?

(124.6 - 4)

3939

Problem Solving and Problem Solving and Dimensional AnalysisDimensional Analysis

How do we convert from one unit of measurement to another?How do we convert from one unit of measurement to another? We do this via We do this via conversion factorsconversion factors..

For instance:For instance:1 dollar = 100 pennies1 dollar = 100 pennies

Both represent the Same Amount of MoneyBoth represent the Same Amount of Money

Conversion factorsConversion factors allow us to carry out conversions between allow us to carry out conversions between different units that mean the same quantity.different units that mean the same quantity.

They are not taken into sig fig consideration.They are not taken into sig fig consideration. Found on A-11 thru A-13.Found on A-11 thru A-13.

4040


Convert 57.4 m into mmConvert 57.4 m into mm

Convert 6.1 dm into kmConvert 6.1 dm into km

Convert 8.1 mConvert 8.1 m22 to cm to cm22

31000mm57.4m 57.4 x 10 mm

1m

4141


Convert 1.06 in. into cmConvert 1.06 in. into cm

Convert 23.80 L into galConvert 23.80 L into gal

Convert 7.62 g/mL into oz./galConvert 7.62 g/mL into oz./gal

4242

Comparing Temperature ScalesComparing Temperature Scales

4343

Temperature ConversionsTemperature Conversions

Converting Between the Kelvin and Celsius Converting Between the Kelvin and Celsius ScalesScales

TToCoC + 273.15 = T + 273.15 = TKK

Converting between the Fahrenheit and Converting between the Fahrenheit and Celsius ScalesCelsius Scales

TToFoF = 1.80(T = 1.80(ToCoC) + 32) + 32

4444

Temperature ConversionsTemperature Conversions

Convert 172 K to Convert 172 K to ooC.C.

Convert 41.2Convert 41.2ooC to C to ooF.F.

Convert 239.05 Convert 239.05 ooF to K.F to K.

4545

DensityDensity DensityDensity: Amount of matter present in a given : Amount of matter present in a given

volume of substancevolume of substance Density = mass/volume = g/mLDensity = mass/volume = g/mL

Not to be confused with weight!Not to be confused with weight!

4646

Example Example

The volume of a liquid The volume of a liquid in a graduated cylinder in a graduated cylinder is 24.00 ml, and weighs is 24.00 ml, and weighs 36.0 grams. What is the 36.0 grams. What is the density of this liquid?density of this liquid? m 36.0 g g

D = = 1.50V 24.00 mL mL

4747

PracticePractice

Mercury has a density of 13.6 g/ml. What Mercury has a density of 13.6 g/ml. What volume of mercury must be taken to obtain volume of mercury must be taken to obtain 100 grams of the metal?100 grams of the metal?

1 matter matter: anything that occupies space and has mass

Documents

chemical properties

chemical changes slide

composition properties

pure substances

boiling point slide

heterogeneous mixture

mixtures mixture

simpler substances