Summary of the three States of Matter ALSO CALLED PHASES, HAPPENS BY CHANGING THE TEMPERATURE ANDOR

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Summary of the three States of MatterALSO CALLED
PHASES, HAPPENS BY CHANGING THE TEMPERATURE
AND/OR PRESSURE OF A SUBSTANCE.

• GAS total disorder mostly empty space
  particles have complete freedom of motion
  (vibrational, rotational, translational)
  particles are very far apart.
• Cool or compress (increase pressure) a gas to
  make a liquid
• Heat or reduce pressure of a liquid to make a gas
• LIQUID Disorder particles or clusters of
  particles are free to move relative to each other
  (vibrational rotational) particles are
  relatively close to each other.
• Cool or compress (increase pressure) a liquid to
  make a solid
• Heat or reduce pressure of a solid to make a
  liquid
• SOLID order ranges from amorphous(slightly
  disordered) to crystalline (ordered) particles
  are essentially in fixed positions (vibrational
  only) particles are close to each other.

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PHASE TRANSITIONS Consider the following phase
changes and properly fill-in the schematic shown
below 1. condensation 2. evaporation 3.
freezing 4. melting 5. sublimation 6. deposition
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Physical Changes The substance or mixture does
not alter in atomic composition. Some Physical
Changes are boiling, evaporation, condensation,
freezing, melting, sublimation, and deposition.
Associated with Physical Changes are Physical
Properties like boiling or freezing point,
density, hardness, and state of matter. H2O (l)
? H2O (g) Chemical Changes The substance
changes in its atomic composition, the atoms are
rearranged and new substances are formed. 2 H2O
(l) ? 2 H2 (g) O2 (g)
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Vocabulary to Know Matter Atom Molecule
Element Compound Homogeneous
Mixture Heterogeneous Mixture Extensive
Property Intensive Property Physical
Property Chemical Property Physical
Change Chemical Change
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YES
NO
YES
NO
YES
NO
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LABORATORY APPLICATIONS Define the
following 1. Filtration 2. Distillation 3. Chro
matography 4. Extraction 5. Crystallization
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ELEMENTS to MEMORIZE
Aluminum Al Manganese Mn Antimony Sb Mercu
ry Hg Argon Ar Neon Ne Arsenic As Nickel
Ni Barium Ba Nitrogen N Beryllium Be O
xygen O Boron B Palladium Pd Bromine Br
Phosphorus P Calcium Ca Platinum Pt Carbon
C Plutonium Pu Cesium Cs Potassium K Chl
orine Cl Radium Ra Chromium Cr Radon Rn
Cobalt Co Rubidium Rb Copper Cu Selenium
Se Fluorine F Silicon Si Gallium Ga Sil
ver Ag Germanium Ge Sodium Na Gold Au Str
ontium Sr Helium He Sulfur S Hydrogen
H Tin Sn Iodine I Titanium Ti Iron Fe
Tungsten W Krypton Kr Uranium U Lead Pb
Xenon Xe Lithium Li Zinc Zn Magnesium Mg
Zirconium Zr
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SIX STEPS OF THE SCIENTIFIC METHOD 1. State a
problem 2. Collect Observations 3. Search for
scientific laws to state a relationship between
observed facts 4. Form a hypothesis or a
temporary observation for an observed fact 5.
Develop a theory that provides a general
explanation for observations made over time 6.
Modify a theory to fit new facts
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ACCURACY vs. PRECISION

• Accurate precise inaccurate but
  precise
• inaccurate imprecise

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PRECISION AND ACCURACY 1. Precision refers to
the degree of reproducibility of a measured
quantity. 2. Accuracy refers to how close a
measured value is to the accepted or true
value. Precise (not accurate)
Accurate (not precise) Both
Precise/Accurate
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MEASUREMENTSScientific Notation

• Many measurements in science involve either very
  large numbers or very small numbers ().
  Scientific notation is one method for
  communicating these types of numbers with minimal
  writing.
• GENERIC FORMAT . x 10
• A negative exponent represents a number less than
  1 and a positive exponent represents a number
  greater than 1.
• 6.75 x 10-3 is the same as 0.00675 6.75 x
  103 is the same as 6750

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MEASUREMENTSSignificant Figures

• I. All nonzero numbers are significant figures.
• II. Zeros follow the rules below.
• 1. Zeros between numbers are significant.
• 30.09 has 4 SF
• 2. Zeros that precede are NOT significant.
• 0.000034 has 2 SF
• 3. Zeros at the end of decimals are
  significant.
• 0.00900 has 3 SF
• 4. Zeros at the end without decimals are
  either.
• 4050 has either 4 SF or 3 SF

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SIGNIFICANT DIGITS WORKSHEET 1. Nonzero
integers. Nonzero integers always count as
significant digits. 1492 has ______ significant
digits 2. Zeros. There are three classes of
zeros A. Zeros that precede all nonzero digits
are NOT significant. 0.00162 has ______
significant digits B. Zeros between nonzero
digits are significant. 4.007 has ______
significant digits C. Trailing zeros at the
right end of the number are significant only if
the number contains a decimal point.
200 has ______ significant digits 200.
has ______ significant digits 200.0 has ______
significant digits 200 has ______ significant
digits D. When writing in scientific notation,
all digits count. 2.370 x 10-3 has ______
significant digit 3. Exact numbers can be
assumed to have an infinite number of significant
figures. The 2 in the circumference of a
circle (2?r) formula has ______ significant
digits
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MEASUREMENTSSignificant Figures Calculations

• Significant figures are based on the tools used
  to make the measurement. An imprecise tool will
  negate the precision of the other tools used.
  The following rules are used when measurements
  are used in calculations.
• Adding/subtracting
• The result should be rounded to the same number
  of decimal places as the measurement with the
  least decimal places.
• Multiplying/dividing
• The result should contain the same number of
  significant figures as the measurement with the
  least significant figures.

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WORKSHOP INVOLVING SIGNIFICANT DIGITS 1. For
addition and subtraction, the result has the same
number of decimal places as the least precise
measurement used in the calculation.
Example 12.11 18.0
1.013 2. For multiplication
and division, the number of significant figures
in the result is the same as the number in the
measurement with the fewest significant
digits. (a) 4.56 x 1.4 ________
(b) (4.12 3.636)
_____ 5.7 NOTE Rules for Rounding 1. In a
series of calculations, carry the extra digits
through to the final result, then round off. 2.
If the digit to be removed is A. less than 5,
the preceding digit stays the same. For example,
2.32 rounds to 2.3. B. equal to or greater than
5, the preceding digit is increased by 1. For
example, 3.46 rounds to 3.5.
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DIMENSIONAL ANALYSIS Unit Conversions Common SI
Prefixes Factor Prefix Abbreviation 106 Me
ga M 103 Kilo k 102 Hecto h 101 Dek
a da 10-1 Deci d 10-2 Centi c 10-3
Milli m 10-6 Micro ? 10-9 Nano n 10-12
Pico p
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MEASUREMENTS - METRIC 1. The mass of a young
student is found to be 87 kg. How many grams
does this mass correspond to? 2. How many meters
are equal to 16.80 km? 3. How many cubic
centimeters are there in 1 cubic meter? 4. How
many nm are there in 200 dm? Express your answer
in scientific notation. 5. How many mg are there
in 0.5 kg?
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MEASUREMENTS

• Since two different measuring systems exist,
  a scientist must be able to convert from one
  system to the other.
• CONVERSIONS
• Length ? 1 in 2.54 cm
• ? 1 mi 1.61 km
• Mass ? 1 lb.... 454 g
• ? 1 kg 2.2 lb....
• Volume ? 1 qt 946 mL
• ? 1 L 1.057 qt
• ? 4 qt 1 gal
• ? 1 mL 1 cm3

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MEASUREMENTS - CONVERSIONS 1. The mass of a
young student is found to be 87 kg. How many
pounds does this mass correspond to? 2. An
American visited Austria during the summer
summer, and the speedometer in the taxi read 90
km/hr. How fast was the American driving in
miles per hour? (Note 1 mile 1.6093
km) 3. In most countries, meat is sold in the
market by the kilogram. Suppose the price of a
certain cut of beef is 1400 pesos/kg, and the
exchange rate is 124 pesos to the U.S. dollar.
What is the cost of the meat in dollars per pound
(lb)? (Note 1 kg 2.20 lb)
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TEMPERATURE CONVERSIONS 1. Fahrenheit at
standard atmospheric pressure, the melting point
of ice is 32 ?F, the boiling point of water is
212 ?F, and the interval between is divided into
180 equal parts. 2. Celsius at standard
atmospheric pressure, the melting point of ice is
0 ?C, the boiling point of water is 100 ?C, and
the interval between is divided into 100 equal
parts. 3. Kelvin assigns a value of zero to
the lowest conceivable temperature there are NO
negative numbers. T(K) T(?C) 273.15 T(?F)
1.8T(?C) 32
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Introduction to Density

• Density is the measurement of the mass of an
  object per unit volume of that object.
• d m / V
• Density is usually measured in g/mL or g/cm3 for
  solids or liquids.
• Volume may be measured in the lab using a
  graduated cylinder or calculated using
• Volume length x width x height if a box or V
  pr2h if a cylinder.
• Remember 1 mL 1 cm3

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DENSITY DETERMINATION 1. Mercury is the only
metal that is a liquid at 25 ?C. Given that
1.667 mL of mercury has a mass of 22.60 g at 25
?C, calculate its density. 2. Iridium is a metal
with the greatest density, 22.65 g/cm3. What is
the volume of 192.2 g of Iridium? 3. What volume
of acetone has the same mass as 10.0 mL of
mercury? Take the densities of acetone and
mercury to be 0.792 g/cm3 and 13.56 g/cm3,
respectively. 4. Hematite (iron ore) weighing
70.7 g was placed in a flask whose volume was
53.2 mL. The flask was then carefully filled
with water and weighed. Hematite and water
combined weighed 109.3 g. The density of water
is 0.997 g/cm3. What is the density of hematite?
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• BASIC MATH
• used in Chemistry 101
• The following slides are basic math review.
  Please look the slides over to refresh your
  memory. I assume you already know this material
  and will not cover it in class.
• Some general math equations
• (1) The Generic equation for percent
• ( portion / total ) 100
• (2) The difference/change between two
  measurements
• D X Xfinal - Xinitial

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Mathematical Review

• Fractions Decimals
• A fraction represents division, the numerator is
  divided by the denominator.
• 2/3 is read as 2 divided by 3
• Proper fraction numerator is smaller than
  denominator. Example 3/5
• Improper fraction numerator is larger than the
  denominator. Example 5/3
• A decimal is a fraction with the division carried
  out.
• A decimal is a fraction expressed in powers of
  10.
• 0 . 0 0 1
• ones . Tenths hundredths thousandths

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Mathematical Review

• Algebraic Equations
• Variables are the symbols used to represent a
  measurement.
• For example T is the variable for temperature
  while t is the variable for time.
• To isolate one variable of an equation remember
  to divide if the unwanted variable is on top and
  to multiply if the variable is on the bottom. An
  asterisk represents multiplication.
• A B / C
• to isolate C first rearrange the equation to it
  will read C? Do this by multiplying both sides
  by C (since it is on the bottom of a fraction
  (denominator).
• C A B C / C note C/C 1
• C A B
• Now to isolate C we need to divide by A (it is on
  top of a fraction A/1 A)
• C A / A B / A
• Remember what ever you do to one side you must
  do it to the other side.
• C B / A

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Mathematical Review

• Algebraic Equations
• When multiplication division is mixed with
  adding subtracting, try the multiplication or
  division first.
• (A - D) / (C F) B
• to solve for C, first rearrange the equation to
  it will read C? Do this by multiplying both
  sides by C F (since it is on the bottom of a
  fraction (denominator).
• (A - D) (C F) / (C F) B (C F)
• (A - D) B (C F)
• Now to isolate C we need to divide by B
• (A - D) / B B (C F) / B
• (A - D) / B C F
• Now you can subtract F from both sides.
• (A - D) / B - F C F - F
• (A - D) / B - F C
• which is the same as C (A-D) / B -F
• If A 8, D 2, B 3, F 7
• then C must (8-2) / 3 - 7 -5

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Mathematical Review

• Exponents
• An exponent is a number written as a superscript.
  
• X2 is X-squared or X to the power of 2
• The base (X) is multiplied by itself the number
  of times represented in the exponent(superscript,
  2 in this example).
• 23 or two cubed (2 is the base and 3 is the
  exponent)
• 23 is 2 2 2 4 2 8
• A positive exponent represents a large number
  (greater than one).
• 1 x 103 is 10 10 10 1000 thousand
• A negative exponent represents a small number
  (less than one).
• 1 x 10-3 is (1/10) (1/10) (1/10) 0.001
  thousandths
• When multiplying numbers written with exponents,
  add the exponents. If dividing then subtract the
  exponents.
• x4 x6 x (46) x10 or (2 x 103)(3 x 106)
  6 x 10(36) 6 x 109
• 2x6/7x3 0.2857 x(6-3) 0.2857 x3