CHAPTER 1

AP CHEMISTRY

TYPES OF MATTERTYPES OF MATTER

►PURE SUBSTANCEPURE SUBSTANCE the same throughoutthe same throughout

► ELEMENTSELEMENTS Fixed properties, substance cannot be Fixed properties, substance cannot be

broken down chemicallybroken down chemically

► COMPOUNDSCOMPOUNDS Two or more elements chemically Two or more elements chemically

bonded, fixed properties, can be broken bonded, fixed properties, can be broken down chemicallydown chemically

PHYSICAL PHYSICAL PROPERTIES/CHANGESPROPERTIES/CHANGES

► PropertiesProperties Can be measured and will usually be the sameCan be measured and will usually be the same Color, density, boiling point, melting point, Color, density, boiling point, melting point,

hardnesshardness

► ChangeChange Properties remain the same throughout a Properties remain the same throughout a

physical changephysical change

► Phase changePhase change SolidSolid, , liquidliquid, , gasgas

► Mass or volume changeMass or volume change

CHEMICAL CHEMICAL PROPERTIES/CHANGESPROPERTIES/CHANGES

►PropertiesProperties The way a substance reacts with another The way a substance reacts with another

substancesubstance

► ChangesChanges Identity of the substance is alteredIdentity of the substance is altered

MIXTURESMIXTURES►HOMOGENEOUSHOMOGENEOUS

Uniformly mixed, all in the same phaseUniformly mixed, all in the same phase

► HETEROGENEOUSHETEROGENEOUS Not uniformly mixed, different phasesNot uniformly mixed, different phases

► CAN BE SEPERATED BY PHYSICAL CAN BE SEPERATED BY PHYSICAL MEANSMEANS

MEASUREMENTS PAGE 8MEASUREMENTS PAGE 8

►LENGTHLENGTH► BASIC UNIT - METERBASIC UNIT - METER

1m = 101m = 1022 cm = 10 cm = 10-3-3kmkm

1nm = 101nm = 10-6-6 mm = 10 mm = 10-9-9 m m Common unit prefixes - kilo, centi, milli, Common unit prefixes - kilo, centi, milli,

nano nano ► MASSMASS► BASIC UNIT KILOGRAMBASIC UNIT KILOGRAM

COMMON PREFIXESCOMMON PREFIXES Kilo, milli, megaKilo, milli, mega

TEMPERATURETEMPERATURE►UNITUNIT

CELSIUS - CELSIUS - ooCC FAHRENHEIT - FAHRENHEIT - OOFF KELVIN - KKELVIN - K

► Temperature is the factor that Temperature is the factor that determines the direction of heat flowdetermines the direction of heat flow

► Temperature is measured indirectly by Temperature is measured indirectly by measuring its effect upon the properties measuring its effect upon the properties of a substanceof a substance

RELATIONSHIP BETWEEN RELATIONSHIP BETWEEN CELSIUS AND FAHRENHEITCELSIUS AND FAHRENHEIT

►Celsius and Fahrenheit when Celsius and Fahrenheit when compared to each other form a linear compared to each other form a linear lineline y = mx + b B = y when x is 0y = mx + b B = y when x is 0 m = m = yy22 - y - y11 T Tff = T = Tcc(9(9ooF/5F/5ooC) + 32C) + 32

xx22 - x - x11

► Boiling and melting pointsBoiling and melting points

CELSIUS AND KELVINCELSIUS AND KELVIN► Kelvin is known as the absolute scale, used Kelvin is known as the absolute scale, used

in chemistryin chemistry 0K = -273.15 0K = -273.15 ooCC TTKK = T = TCC + 273.15 + 273.15

ENERGYENERGY► SI unit is JouleSI unit is Joule

1J = 1 N1J = 1 N..m = 1 kgm = 1 kg..mm22/s/s22

► Relationship between calories and JoulesRelationship between calories and Joules 1cal = 4.184 J1cal = 4.184 J

► PROPERTIESPROPERTIES INTENSIVEINTENSIVE The value is not dependent on the The value is not dependent on the

amount of material you haveamount of material you have► EXTENSIVEEXTENSIVE

Depends on the amountDepends on the amount

UNCERTAINITY IN UNCERTAINITY IN MEASUREMENTSMEASUREMENTS

► Every measurement has a degree of Every measurement has a degree of uncertainty. Human error or balances that uncertainty. Human error or balances that are calibrated differently.are calibrated differently.

► ACCURATEACCURATE How close the measurements are to the How close the measurements are to the

“true” value“true” value► PRECISIONPRECISION

How close an individual measurement is How close an individual measurement is to other measurementsto other measurements

DERIVED UNITSDERIVED UNITS

► VOLUMEVOLUME SI unit is mSI unit is m33

1cm1cm33 = (10 = (10-2-2 m) m)33 = 10 = 10-6-6 m m33

1L = 1000 mL =1000 cm1L = 1000 mL =1000 cm33

► FORCEFORCE SI unit is NewtonSI unit is Newton 1N = 1kg1N = 1kg..1m/s1m/s22

► PRESSUREPRESSURE SI unit is PascalSI unit is Pascal 1Pa = 1N/m1Pa = 1N/m22

Standard atmosphere is 1.013 x 10Standard atmosphere is 1.013 x 1055 Pa Pa

SIGNIFICANT FIGURESSIGNIFICANT FIGURES► ATLANTIC-PACIFIC RULEATLANTIC-PACIFIC RULE

If a decimal point is If a decimal point is PPresent then count the resent then count the significant figures from the left (significant figures from the left (PPacific side). acific side). Start with the first nonzero number ----> Start with the first nonzero number ----> 0.073020.07302

If a decimal point is If a decimal point is AAbsent then count the bsent then count the significant figures from the right (significant figures from the right (AAtlantic tlantic side). Start with the first nonzero number side). Start with the first nonzero number 40978000 <-40978000 <-

SIGNIFICANT FIGURESSIGNIFICANT FIGURES► State of degree of confidence in the measurement State of degree of confidence in the measurement

citedcited► Nonzero integers:Nonzero integers:

Nonzero integers are always significantNonzero integers are always significant► Zero’s. There are three classes or zero’sZero’s. There are three classes or zero’s

Leading zero’s precede (before) all nonzero Leading zero’s precede (before) all nonzero digits. ARE NOT SIGNIFICANT 0.0025digits. ARE NOT SIGNIFICANT 0.0025

Captive zero’s are between two nonzero digits. Captive zero’s are between two nonzero digits. ARE SIGNIFICANT 1.109ARE SIGNIFICANT 1.109

Trailing zero’s are to the right of nonzero Trailing zero’s are to the right of nonzero integers. ONLY SIGNIFICANT IF A DECIMAL POINT integers. ONLY SIGNIFICANT IF A DECIMAL POINT IS PRESENT 57000 and 57000.IS PRESENT 57000 and 57000.

ROUNDING NUMBERSROUNDING NUMBERS► In a series of calculations carry all digits unit the In a series of calculations carry all digits unit the

final solution, THEN ROUNDfinal solution, THEN ROUND► If a digit needs to be roundedIf a digit needs to be rounded

If it is less than 5, the preceding digit remains If it is less than 5, the preceding digit remains the samethe same

► If the digits are equals or is greater than 5, the If the digits are equals or is greater than 5, the preceding digit is increased by one.preceding digit is increased by one.

UNCERTAINITY IN NUMBERSUNCERTAINITY IN NUMBERS► Multiplication and divisionMultiplication and division

Significant figures are the same as the least Significant figures are the same as the least precise (precise (number with the smallest number of number with the smallest number of significant figuressignificant figures) measurements) measurements

► Addition and subtractionAddition and subtraction The answer will have the same number of digits The answer will have the same number of digits

beyond the decimal point as the integer (that beyond the decimal point as the integer (that was added or subtracted) with the least accurate was added or subtracted) with the least accurate number (number (last significant number is in the highest last significant number is in the highest place holderplace holder) )

PERCENT ERRORPERCENT ERROR►When doing an experiment it is When doing an experiment it is

important to see if you did it correctly. important to see if you did it correctly. This can be done if an accepted value This can be done if an accepted value is known. (i.e. density of copper 8.9 is known. (i.e. density of copper 8.9 g/mL). You compare your value to the g/mL). You compare your value to the accepted value by using percent erroraccepted value by using percent error

► Percent = Percent = ││accepted value - experiment accepted value - experiment value│value│ x 100 x 100

Error accepted valueError accepted value

DENSITY, MELTING AND BOILING DENSITY, MELTING AND BOILING POINTSPOINTS

► DENSITYDENSITY Mass/volume, unit = g/cmMass/volume, unit = g/cm33

► Melting pointMelting point Temperature at which solid goes to liquid phaseTemperature at which solid goes to liquid phase

► Boiling pointBoiling point Temperature at which liquid goes to gasTemperature at which liquid goes to gas

► SolubilitySolubility Different compounds have different solubility's at different Different compounds have different solubility's at different

temperaturestemperatures► Usually solubility of a solid goes down as the Usually solubility of a solid goes down as the

temperature goes down (except KOH)temperature goes down (except KOH)