Unit 1: Introduction to Chemistry
Unit 1: Introduction to Chemistry
This alchemist is searching for the Philosophers Stone. He
shouldve just asked Dumbledore.This modern chemist was playing
Solitaire but quickly Alt-Tabbed out as the picture was
snapped.1SafetyThere are two things wrong with this picture. What
are they?1) There is an uncontrolled flame.2) Where are Beakers
goggles?
2Safety IISince we do not want to pull a Beaker, let us visit
our Safety Rules for the classroom.Follow these, or else.Or else
what? You askare you sure you want to know?
3Or else youll be like
thishttp://www.youtube.com/watch?v=V-fNpaOX0-gI dont want you to be
like that.You dont want to be like that.So lets just avoid that
altogether, okay?4Course SyllabusHere it is5Unit 1 ObjectivesIt is
important to work safely and efficiently in the
laboratory.Quantitative data is best organized in tabular or
graphical form.The scientific method is used in problem
solving.Chemistry is a physical science which deals with the
structure of matter.The states of matter are distinguished by their
molecular structure.Matter and energy are related.Physical and
chemical properties are useful to the chemist.The Laws of
Conservation explain many chemical concepts.Significant figures are
used to analyze the accuracy of measurements.The magnitude of a
number is best illustrated with scientific notation.Dimensional
analysis is a logical approach to problem solving.Density is an
intensive physical property.Heat and temperature are related.The SI
system is the scientific system of measurement.6Essential
QuestionsHow do scientists obtain and record consistent data?Could
the scientific method be used to solve any problem?What are the
distinctions between matter and energy?Guiding Questions:What are
safe laboratory procedures?What is the role of observation in
science?How is chemistry defined?Why are chemical and physical
properties important?What is correct scientific notation?When is a
number significant, but not important and when is it important, but
not significant?How are significant figures used in
calculations?What is the difference between accuracy and precision
and how are they measured?How is quantitative data analyzed?How
does the SI system of measurement compare to the English system of
measurement?Why is dimensional analysis used in problem solving?Why
is density important?How are heat and temperature related?Where did
the energy go? Define what a system is and determine if things are
or are not systems.7Your TakeWhat would you like to add?How does a
stylus work on a touchscreen?(P1)Why do coke and mentos create a
fountain?What is the fastest to destroy a potato?Why does helium
make balloons float but air doesnt?Why does radiation come off your
phones? Can it affect you?Why does coke take paint off of cars?What
type of elements are in soda/seltzer? (P3)What is Es used for?What
is element 39?How many elements are in ibuprofen?Is Helium only
used to blow up balloons?What is medical contrast made of?What
gasses make your voice lower?How do we synthesize elements?How many
elements are radioactive?What would you like to add?How does Helium
make your voice higher? (P5)Why does mentos and soda result in an
explosion?What element is the most reactive?How do we synthesize
elements?What are radioactive isotopes of certain elements?Why does
sprite and bananas (gallon of milk) make you vomit?Why does salt
and ice make your arm burn?Why does Purel or colognes/perfumes
burn?Transition lens sunglasses?Why are the transition metals
special on the periodic table?How do iPhone touchscreens work?Why
do onions make you cry?What makes something spicy?What happens when
you open a new bottle re: carbonation?How do pop rocks work?What
gasses change voice higher or lower?What makes glowstitcks glow?How
do ice packs work?Why do air horns get cold as you use them?What
makes glue sticky?How does the atomic bomb work?Why is urine
yellow?
8EnvironmentalStudy of how chemicals and biological materials
react naturallyGreen Chemistry is an attempt to reduce pollution at
the source.Back
24DiscoverySometimes happens by chanceIm looking at YOU,
Columbus!Benzodiazepine (therapeutic drugs, Valium) were forgotten
for over a year and then almost THROWN AWAY before a sample was
retested.Made Hoffman-La Roche MILLIONS of dollarsBut typically the
result of a well developed process26AstrochemistryStudy of
chemistryjust in space. Back
25Minded the GapHow does sugar bridge the gap?Sugar is not a
living substance.However, when utilized, provides the energy for us
to live.
12
What is mind? No matter. What is matter? Nevermind!MatterIt is
VERY important, Homer.This is what chemists study.But what IS it?
For us, matter is anything that has mass and takes up space.So what
is everything else?13Everything ElseEnergy!Lets just say light and
heatNeither have massNeither have volumeBut what if something is
neither matter nor energy?
14That Empty FeelingFor all intents and purposes: nothing.Though
to Laurence Krauss nothing = everything!For us, though, we will see
how most of our being (and therefore everything) is empty.
15Time to study, but where?In your groups, determine what type
of chemist would study the following:1) DNA2) blueberries3)
cis-2-butene4) Zeolites5) C13 NMR6) Phase change7) Room-temperature
Superconductors8) Contaminants16Branches of the Chemistree
OrganicInorganicAnalyticalBiochemistryPhysicalTheoreticalEnvironmentalMove
OnAstrochemistry17The Scientific MethodThe logical problem solving
approachBut what is the order?If you do not remember the exact
word, you can describe the step.
27ObservationThe most important tool in any scientists
arsenal.Obtain qualitative (descriptive) and quantitative
(numerical) data.
28HypothesizeIt is impossible to develop an experiment without
having something to test.The testable statement is the
hypothesisGeneralization of your observed data
29Testing (Experimentation)An attempt to validate the
hypothesisConditions may be constant (control)Or changing
(variable)
30Analysis of DataALL data is importantIt can relate directly to
your experimentIt can lead you down a new path of discoveryProperly
organized using tables, charts, graphs, calculations.
31ConclusionThis is when you attempt to explain resultsModel: an
explanation to how the observed phenomena occurs (Atomic
Model)Theory: a broad generalization that explains a body of facts
(Evolution)
32MeasurementsIn the course of obtaining data, often times
different tools are used and different numbers are recorded.This is
expected and not a sign of making mistakes.However, for clarity and
consistency, we may need to make adjustments.33Taking
MeasurementsHave you ever heard that a humans wingspan is equal to
their height?Can be seen in Da Vincis Vitruvian Man
34Lets Test ItAt each table, measure the wingspan and height in
using meters (cm and mm too)Find the ratio height / wingspanPlace
your results on the board.Is Da Vinci correct?35Significant
FiguresAdd the following2.105103.342.941.3013What do you get?
36Significant Figures IIDid you get 149.6463?Is that correct?Are
you sure?Did your calculator tell you?Remember your calculator is
only going to do what you TELL it to, not what you WANT it to
do.Are you still sure?37Significant Figures IIIWhat about now
1.3013 2.105 42.94103.3Notice anything?Still think it is
149.6463?38Significant Figures IVHere is the big problem 1.3013
2.105 42.94103.3 149.6463Do you know what these #s are?
39Significant Figures VWe CANNOT say those ?s are 0. There is a
1 in 10 chance each ? is a 0 which means (1/10)^6 or a1 in a
MILLION chance the answer is 149.6463! 1.3013 2.105 42.94103.3
149.6463So what IS the answer?40Significant Figures VIWe can only
say for sure each number to their 1st decimal (tenths)
place.Therefore, our answer must reflect that 1.3013 2.105
42.94103.3 149.6463So the answer is 149.641Significant Figures
VIIWhen multiplying and dividing, the process is similar.Take 1.5 x
1.3 = 1.95My original numbers only contained TWO (significant)
digits, how can my answer contain three?Hint: it cannot!So what to
do about it?1.9 or 2.042Significant Figures VIII9.6134 5.780 =
=1.663217993Similar to the addition/subtraction rules, since my two
original numbers have different significant digits, my answer must
reflect the LEAST amount, therefore only 4 can be
shown.1.66321799343Scientific NotationWhen numbers obtained are
REALLY big or REALLY small, there are a lot of digits:The Spaces
added within the number are for clarificationAvogadros Number
(amount)602 214 179 000 000 000 000 000Mass of the electron
(kg)0.000 000 000 000 000 000 000 000 000 000 9109 44Scientific
Notation IIThe purpose of scientific notation is to shorten the
number by eliminating as many zeros as possible.Avogadros Number
(amount)6.02214179 x 1023Mass of the electron (kg)9.109 x
10-3145Scientific Notation IIIBefore some example
demonstrationsNote the following1) Values greater than 1 have a
positive exponent2) Decimal values (between 1 and 0) have a
negative exponent3) The value of the exponent represents the number
of places the decimal moved46Accuracy and
PrecisionAccuracycloseness of a measurement to an accepted valueIn
other words, how close to the target or goal are
you?Precisioncloseness of a set a measurementsWere going to need an
example47Our TargetIn order to compare the accuracy of the upcoming
event, we need to base the determination on Calvins location.To
gauge the precision, we need to look at the location of the various
projectiles.
48MeasurementWhat can I say? Science is messy sometimes.
49Accurate or Precise?Accuracy: Certainly so as Calvin got hit
numerous times.Precise: the snowballs are in a close location to
other snowballs.
50Accuracy and Precision IIBoth A & P close to goal and
selfA, not P close to goal, not selfP, not A close to self, not
goalNeither A nor P Not close to self nor goalHow accurate,
precise, or neither are you?
51SI SystemOur Standard system of measurement includes numerous
oddities:1 gal = 4 qt = 16 cups = 256 tbsp = 768 tspThe SI System,
once mastered, is much easier to use if you know how to move a
decimal!
52Why SI?Mars Climate Orbiter$300,000,000+ mission to Mars
Mission FailedTake a guess as to why.Different pieces of software
used different units!One program used English unitsAnother used
metric (SI)Orbiter entered the Martian atmosphere and
disintegrated.53SI System IIThe International System has numerous
units. Identify the ones for:1) Length2) Time3) Temperature4)
Amount5) Mass6) Area7) Volume8) Density9) Molar mass54SI System
IIIThe units we will often use are as follows1) Length meter (mm,
cm, m)2) Time second (s)3) Temperature Kelvin (K)4) Amount mole (n
or mol)5) Mass mass (g or kg)6) Area meter squared (cm2 or m2)7)
Volume cm3, mL, and L most common8) Density g/cm3 or g/mL most
common9) Molar mass g/mol55SI System PrefixesKing Henry Died by
Drinking Chocolate MilkYou may remember this mnemonic deviceIf so,
what does it mean?
56SI System Prefixes IIKing = kilo (k)Henry = hecto (h)*Died =
deca (da)*By = base Drinking = deci (d)*Chocolate = centi (c)Milk =
milli (m)*Rarely used by us
57SI System Prefixes IIIA numerical look at the prefixes shows
us:Kilo = 1000Hecto* = 100Deca* = 10Base = 1 (1 gram, 1 liter, 1
meter)Deci* = 0.1Centi = 0.01Milli = 0.001*Although we will not
measure these units, they are important to remember for
conversions!
58Prefix ConversionsSometimes it makes more sense to alter how a
number is recorded1 000 000 micrometers or 1 meter?As long as we
know1) Where the decimal is2) The original unit3) The new unitWe
can convert numbers easily
59Dimensional AnalysisIf someone asked you how many minutes were
in a year, do you know?If you have seen Rent, yes.If you have not,
dont despair.How many days in a year?How many hours in a day?How
many minutes in an hour?Do you know THOSE answers?If so, you can
figure it out.60Dimensional Analysis IISo how do we know the number
of minutes in a year?1 year = 365 days1 day = 24 hours1 hour = 60
minutesWe can use these as conversion factors1yr x 365days/1yr x
24hr/1day x 60min/1hr= 525,600 minutes61DensityDensity is a common
property which compares a mass per unit of volumeVery useful
information, especially for identification purposes.
62Density = mass / volumeD = m/VCommon units are g/cm3 or
g/mLSolidD @ 20*CLiquidD @
20*Ccork0.24gasoline0.67ice0.92ethanol0.791bone1.85water0.998diamond3.26sea
water1.025lead11.35mercury13.663
