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IntroductionIntroduction CHEM 012: Chemical Principles CHEM 012: Chemical Principles
Sections 66-78Sections 66-78Fall 2006Fall 2006
Instructor:Instructor: Dr. Arshad KhanDr. Arshad KhanOffice:Office: 107 Chemistry Blg107 Chemistry Blg
Phone:Phone: (814) 863-9295(814) 863-9295Office hours:Office hours: Weds. 10:30-noon Weds. 10:30-noon
or by appt.or by appt.Email:Email: [email protected]@psu.edu
TAs will be assisting us with this course &TAs will be assisting us with this course &
will be available to help you at their posted will be available to help you at their posted
hours hours
Chem Undergrad Office: 210 Whitmore(814) 865-9391
Grades
Recitation days: Quiz & HomeworkOnline skill check tests3 Midterm exams & a final
Chapter 1Chapter 1Matter and MeasurementMatter and Measurement
Chem 12Chem 12
Penn State Penn State
Dr. Arshad KhanDr. Arshad Khan
States of MatterStates of Matter
Solid Solid Fixed shape, fixed volume, incompressible, Fixed shape, fixed volume, incompressible,
particles are closely spaced and strongly held.particles are closely spaced and strongly held.
LiquidLiquid No fixed shape, fixed volume, almost No fixed shape, fixed volume, almost
incompressible, particles are less strongly held.incompressible, particles are less strongly held.
GasGas No fixed shape, no fixed volume, compressible, No fixed shape, no fixed volume, compressible,
particles are loosely heldparticles are loosely held
States of MatterStates of Matter
SI UnitsSI Units
Length : Meter (m)Length : Meter (m) Mass: Kilogram (kg)Mass: Kilogram (kg)
Prefixes used in Metric SystemPrefixes used in Metric System
Giga (G):Giga (G): 101099
Mega (M): Mega (M): 101066
Kilo (K):Kilo (K): 101033
Deci (d):Deci (d): 1010-1-1
Centi (c):Centi (c): 1010-2-2
Milli (m) :Milli (m) : 1010-3-3
Micro (μ) :Micro (μ) : 1010-6-6
Nano (n) :Nano (n) : 1010-9-9
Pico (p) :Pico (p) : 1010-12-12
Femto (f) :Femto (f) : 1010-15-15
Note: 1 kg = 103 g 1 km = 103 m
Temperature ScalesTemperature Scales
K = oC + 273.15oC = (5/9) (oF – 32) or oF = (9/5) (oC) + 32
(100 div./180 div.)
DensityDensity = Mass (g) / Volume (mL) = g/mL
Extensive PropertyExtensive Property depends upon massdepends upon mass Examples: volume, heatExamples: volume, heat
Intensive PropertyIntensive Property does not depend upon does not depend upon massmass Examples: Color, Temperature, boiling Examples: Color, Temperature, boiling
temperature, etc.temperature, etc.
Physical & Chemical ChangesPhysical & Chemical Changes
Physical & Chemical ChangesPhysical & Chemical Changes
Uncertainty in MeasurementUncertainty in Measurement
PrecisionPrecision ReproducibleReproducible
AccuracyAccuracy Correct and ReproducibleCorrect and Reproducible
How are they different?How are they different?
Precision means reproducible & may be correct or Precision means reproducible & may be correct or incorrectincorrect
Significant FiguresSignificant Figures
1.1. Left most nonzero digit is the most Left most nonzero digit is the most significant figure (MSF).significant figure (MSF).
2.2. When there is a decimal point, the right When there is a decimal point, the right most digit is the least significant figure most digit is the least significant figure (LSF).(LSF).
3.3. The number of digits from the MSF to the The number of digits from the MSF to the LSF is the number of significant figures.LSF is the number of significant figures.
12.3100
MSF LSF (6 significant figures)
1234 = 1 .234 x 103
*no decimal point MSF LSF(4 significant figures)
1200 = 1.2 x 103 (2 significant figures)1.20 x 103 (3 significant figures)
1.200 x 103 (4 significant figures)
0.00520 = 5.20 x 10-3 (3 significant figures)
Exact Numbers12 inches = 1 foot12.000000… (∞ significant figures)
Rules of Multiplication & DivisionRules of Multiplication & Division
Go by minimum number of significant figuresGo by minimum number of significant figures1.01.0 xx 5.36425.3642 == 5.35.36426422 sig.2 sig. 5 sig.5 sig. Drop and round offDrop and round off
fig.fig. figfig..
== 5.45.4 Round off ruleRound off rule
When dropping a digit greater than 5, add 1 to the When dropping a digit greater than 5, add 1 to the preceeding digit.preceeding digit.
When dropping a digit equal to 5, add 1 for odd When dropping a digit equal to 5, add 1 for odd preceeding digit; otherwise, do not add.preceeding digit; otherwise, do not add.
Rule of Addition & SubtractionRule of Addition & Subtraction
Go by minimum number of decimal places Go by minimum number of decimal places (dp).(dp).
0.10.1 ++ 22.3222.32 == 22.422.422
1 dp1 dp 2 dp2 dp drop drop
= = 22.422.4
Dimensional AnalysisProblems