... alpha typing calculators allowed during tests/quizzes) MasteringChemistry
access code (access to online assignments, e-book, tutorials, powerpoints, etc.).
Chapter 1
Chemistry 1A
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Beginning: Materials: Chemistry: A Molecular Approach, Tro, 4th edition, Pearson, 2017, Chem 1B Lab Manual, Dept. of Chemistry at Moorpark College, Safety Glasses, and Scientific Calculator with exponential and logarithmic functions (no cell phones, graphing, programmable, alpha typing calculators allowed during tests/quizzes) MasteringChemistry access code (access to online assignments, e-book, tutorials, powerpoints, etc.) How to start: Review the math found in Appendix. If the math in Appendix is difficult to follow, consider taking more algebra before attempting Chemistry 1A. It is expected that students in Chemistry 1A have a background in chemistry; therefore the material is covered quickly and intensely. Read, study and work problems often and regularly to keep up. Look over materials and websites. Notice the appendices I-IV and glossary in the textbook as well as resources in MasteringChemistry. We cover Chapters 1-13 in Chemistry 1A. When starting a new Chapter read the contents (section titles) found on the first page of the chapter, chapter in Review at the end. After you have a general overview of the upcoming material read the chapter text before coming to lecture and a second time after the material is covered in lecture. Work out the examples and problems and work a variety of the end of chapter homework problems for practice and greater understanding. Syllabus:
Refer to the syllabus often to know the class expectations, laboratory activities (experiments, formal lab write-ups, and workshops), test days, etc. More help: Your instructor has office hours set aside each week for assistance. The learning center in the library often has tutors that may help in math and chemistry. It is recommended that you exchange co Look over the lab assignment before attending the labs
ntact information with others in the class to assist in forming study groups, assist with getting a ride to school when your car does not work, having someone to ask a question regarding class, or after missing a class to find out what was covered.
Chapter 1
Chemistry 1A
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Chapter 1: Matter, Measurement and Problem Solving Homework: Read Chapter 1 and work out sample/practice exercises and end of chapter problems for more practice. Look over the lab assignment before attending the labs Memorize the names (correct spelling) and symbols (capitalize only the first letter) of the 44 common elements in the handout. Register for and start the homework online through MasteringChemistry Chemistry: The science that seeks to understand the behavior of matter by studying the behavior of atoms, molecules and compounds. The study of the composition, properties, and transformations of matter. Matter: Anything that has mass and occupies space. Matter is composed of atoms, molecules, and compounds Atoms and Molecules: Matter, composition, structure, element, atom, molecule, compound; chemical bonds. All things are made of atoms.
This image shows the Kanji for “atom” written with individual Fe atoms on top of Cu
Chapter 1
Chemistry 1A
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The Scientific Method: A systematic procedure for solving problems and exploring natural phenomena. Chemists employ the scientific method, which makes use of observations, hypotheses, laws, theories, and experiments. Observations (data; a series of measurements or observations) o observations are the foundation of the scientific method o Some observations are made with the naked eye, while others rely on instrumentation. o data can be qualitative descriptions or quantitative measurements. o Scientific data may be graphed to see relationships. o data is most useful when collected under controlled conditions, experiments Hypotheses o tentative explanations to interpret the observations o a useful hypothesis must be testable o must be rejected or corrected when they conflict with experiment Experiments o experiments must be repeatable and reproducible Practical use of the Scientific Method… Observation/Problem: The lamp in the bedroom will not light/turn on. Possible hypotheses: Come up with some testable hypothesis from your experience
Experiments: From each hypothesis, an experiment can be conducted to test the hypothesis/explanation. More observations are obtained through experiments and over time, a good hypothesis/explanation is repeatable and reproducible. What experiments can be performed to check your hypothesis?
Chapter 1
Chemistry 1A
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The cycle of the scientific method is repeated many times with rejections, alterations, improvements and support. Numerous observations and experiments lead to Scientific Laws and Theories. Scientific Laws come from observations (also called natural laws) compactly summarize patterns and results of a large number of observations predicts future observations may apply only under special conditions are descriptions of nature that predict future outcomes, not explanations A few examples of Natural Laws(also known as Scientific Laws or just Laws)… 1. Newton’s Laws of Motion 2. Dalton’s Law of Partial Pressures 3. Lavoisier’s Law of Conservation of Mass Scientific Theories come from hypotheses Are well-tested models that explain and give the underlying causes for observations and laws. Discarded or refined when they can't explain new experimental results A good theory... explains currently available data is as simple as possible (but no simpler!) accurately predicts results of future experiments suggests new lines of work and new ways to think clearly shows underlying connections A few examples of Theories… 1. Heliocentrism (1543, Copernicus) 2. Evolution (1859, Darwin) 3. Quantum Theory (Max Planck, Einstein, Niels Bohr, Werner Heisenberg, Erwin Schrödinger, Max Born, Paul Dirac, 1900–1926)
Chapter 1
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The Scientific Method (Do you understand it?) 1.
A number of people become ill after eating dinner in a restaurant. Which of the following statements is a hypothesis? a) The cooks felt really bad about it. b) Bacteria in the oysters may have caused the illness. c) Everyone who ate oysters got sick. d) Symptoms include nausea and dizziness e) People got sick whether the oysters were raw or cooked
2.
The Scientific Method a) is just a theory b) is a strict set of rules and procedures that lead to inarguable fact. c) isn't used much in modern chemistry. d) is based on continued observation and experiment. e) is a framework for proving an argument you know to be true.
3.
Which of the following statements is TRUE? a) A scientific law explains an observation. b) Once a theory is constructed, it is considered fact. c) A hypothesis is speculation that is difficult to test. d) An observation explains why nature does something. e) A scientific law summarizes a series of related observations.
4.
Classify each of the following as an observation (O), a law (L), or a theory (T)
_____
a) Matter is made of atoms
_____
b) Matter is conserved in chemical reactions
_____
c) When wood burns in a closed container, its mass does not change
_____
d) A body in motion stays in motion unless acted on by a force
_____
e) The universe began as a cosmic explosion called the Big Bang
_____
f) A stone dropped from 450 meters falls to the ground in 9.6 seconds.
Chapter 1
Chemistry 1A
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Element: A fundamental substance that cannot be chemically changed or broken down into anything simpler. All elements are made from stardust. About 90 are naturally occurring. 75% of the observed mass of the universe is H Percentage of Elements by Mass in the Earth
Percentage of Elements by Mass in the Human Body
Chapter 1
Chemistry 1A
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Memorize the names (correct spelling) and symbols (capitalize only the first letter) of the 44 common elements in the handout. Historical Notes: pottery and ceramics, glass, embalming, bronze age, metals, Chinese (Yin, Yang), Greek (Earth, Wind, Fire, Water, Ether), alchemy, scientific method. Periodic Table: 1789 French scientist Antoine Lavoisier first tabulated the known elements (24) 1829 Johann Dobereiner observed triads (Ca, Sr, Ba and Cl, Br, I and Li, Na, K), by 1843, sixteen triads were known. 1869 Russian chemist Dmitri Mendeleev placed elements in 7 horizontal rows (Periods) and 18 vertical columns (Groups). Elements in a group behaved similarly. Main groups, transition metals, inner transition metals(rare earth metals) Alkali metals, alkaline earth metals, halogens, noble gases Metals, semimetals (metalloids), nonmetals
Chapter 1
Chemistry 1A
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The Study of Chemistry: Chemistry: The study of the composition, properties, and transformations of matter. 1. 2.
Atomic and Molecular Perspective- Matter, composition, structure, element, atom, molecule, compound, Why Study Chemistry –Chemistry provides important understanding of our world/universe and how it works. It is a very practical science that has improved our daily lives. It is the foundation that provides the basic language required for many other science and technological fields.
Classifications of Matter: States of Matter: solid
liquid
gas
Properties: (shape, volume, energy content, phase changes, endothermic vs. exothermic). Solids may be crystalline or amorphous
Chapter 1
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Pure Substances Pure substances have one invariable composition independent of how they were formed. elements (memorize the common elements and symbols for quiz) molecules compounds. Mixtures: Mixtures have a variable composition Heterogeneous: composition varies from one region to another Homogeneous: uniform composition
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Separation Mixtures: Different components have different physical or chemical properties which enable separations. Distillation:
Evaporation:
Decanting:
Filtration:
Chromatography: paper, liquid, gas
Chapter 1
Chemistry 1A
Properties of Matter:
1.
Physical: A property or change that does not change the chemical composition such as… change of state, separation of mixtures (decantation, filtration, evaporation, distillation, chromatography), temperature, odor.
2.
Chemical: A property or change that does involve a change in the chemical makeup such as… Elements to compounds, reactants forming a different compound, change in chemical structure and composition, rusting (oxidation of metals), combustion, and decomposition.
3.
Intensive: Property is independent of the amount… density, melting point, color
4.
Extensive: Property is dependent of the amount… mass, volume, and length
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Chapter 1
Energy:
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Energy is the capacity to do work. Work is force applied across a distance, push or pull on an object. Energy can be converted from one form to another. When matter undergoes a chemical or physical change, the amount of energy in the matter also changes. Potential energy
Kinetic energy
Thermal energy is a form of kinetic energy as the molecules are moving.
Law of Conservation of Energy
Spontaneous processes prefer the direction that will lower energy
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Units of Measurement: SI Units (Systéme International d’Unités) chosen by international agreement in 1960 based on the metric system. Physical Quantity Unit Abbreviation kilogram kg Mass meter m Length Kelvin K Temperature mole mol Amount second s Time ampere A Electric current candela cd Luminous intensity liter L Volume (derived unit), dm3 3 Solid, liquid: g/cm3=g/ml, Density (derived unit), mass/V kg/m for gases: g/L J Energy (derived unit), kgm2s-2 joule Prefixes used in the metric system. Prefix Abbrev. Meaning G 109 Giga
Example 1 Gigabyte = 1 x 109 bytes
Mega
M
106
1 Megameter = 1 x 106 meter
kilo
k
103
1 km = 1 x 103 m
unit
-
1
1
deci
d
10-1
10 dm = 1 m
centi
c
10-2
102 cm = 1 m
milli
m
10-3
103 mm = 1 m
micro
10-6
106 m = 1 m
nano
n
10-9
109 nm = 1 m
pico
p
10-12
1012 pm = 1 m
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Know these Common Conversions. (more in textbook) Length 2.54cm = 1 inch 1 km = 0.621 mi 453.6 g = 1 pound (lb) 1 kg = 2.205 pounds (lbs) Mass Volume
1 ml = 1 cm3 = 1 cc
Temperature °C = K -273.15 K = (°C) + 273.15 Energy
4.184 J = 1 calorie
Temperature: Derive the temperature conversion formulas: y = mx +b Choose x as Celsius to have a simple y intercept (b)
946 ml = 1 qt °F = 1.8(°C) + 32 °C =
[(°F) – 32] 1.8
1.602 x 10-19 J = 1 eV
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Chemistry 1A
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Uncertainty in Measurement: Inexact (has uncertainty) Exact (definitions: i.e. 1 ft = 12 in, or whole items: i.e. number of students enrolled) Precision (measurements agree with each other) Imprecision in measurements may be caused by random or systematic errors. Random error (no specific cause, cannot be corrected) Systematic error (caused by limitations in technique, experimental design, or instrument calibration, can be reduced) Accuracy (measurement agrees with true value) Significant Figures-only the last digit is estimated/uncertain. What is your estimated reading for the graduated cylinder? Rules for significant figures: 1000mm = 1 m
Numbers 1 through 9
Unlimited significance Significant
Leading zero
Never significant
0.00402 kg
Captive zero between nonzero
Significant
2.005 x 108 atoms
Trailing zero with decimal
Significant
3.200 x 104 s
Trailing zero without decimal
Uncertain
1400 miles
Exact numbers
Significant Figures in Calculations: 1. 2.
Addition and Subtraction-minimum significant to the right taken Multiplication and Division-least number of significant numbers
25.223 g
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Rounding Numbers: Remove all nonsignificant numbers. Less than 5 round down (drop it), when 5 or more round up. Scientific Notation: When writing very large or very small values it is best to remove the placeholder zeroes and keep all the significant numbers. Scientific notation keeps one digit before the decimal, remaining significant figures after the decimal, and multiplies by a factor of ten (negative power for small munbers and positive for large numbers. ?.??? x 10? 12,300,000 min = 1.23 x 107 min
0.000 000 000 765 m = 7.65 x 10-10 m
Dimensional Analysis: 1. 2. 3. 4. 5. 6. 7. 8.
Aids problem solving using conversion factors/definitions Always write every number with its unit Always include units in calculations Use conversion factors to generate equivalence statements Arrange conversion factors to cancel starting units May string conversion factors together When squaring a conversion factor one must square both the number and unit, When cubed, number and unit must be cubed Round off at the final step, do not round progressively Sort, Strategize, Solve, Check
Practice Problems: 1.
One lead has a mass of 0.000 000 000 000 000 000 000 3441 g. Express this in proper scientific notation.
2.
Indicate the number of significant figures in each and write in Scientific Notation. a) 0.000343 km b) 645,000,000 ml
Chapter 1
Chemistry 1A
3.
Convert 8.22 x 102 nanoliters/min into units of quarts/year.
4.
The average surface temperature of the South Pole is -56C.
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a) What is this temperature in Kelvin?
b) What is this temperature in Fahrenheit?
5.
A student finds that the weight of an empty beaker is 53.583 g. She places a solid in the beaker to give a combined mass of 57.483 g. To how many significant figures is the mass of the solid known?
6.
A 3.00 quart container weighs 302 grams when empty. When it is filled with liquid, the container weighs 2.412 kilograms. What is the density of the liquid in g/ml?
7.
Describe the difference between experimental data which is accurate and data which is precise. Give examples. What is the difference between random and systematic errors?
Chapter 1
8.
Chemistry 1A
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Place a P before a physical property or change and a C before a chemical property or change: The reaction with zinc and hydrochloric acid to produce a gas Crystallization of CuSO4 by evaporation of its aqueous solution Metals are shiny, malleable, ductile, good conductors of heat and electricity Alkali metals combine with halogens in a 1:1 ratio to form a compound
9.
10.
For the following identify each in as many ways as possible using the following: a) matter, b) pure substance, c) compound, d) molecule, e) element f) homogeneous mix g) heterogeneous mix h) metal i) nonmetal j) ionic compound k) alloy n) none a)
Oxygen, O2
b)
Sodium bromide, NaBr
c)
Cu-Zn alloy called brass
d)
Burrito
e)
Potassium
f)
Hypothesis
Monel metal is a corrosion-resistant copper-nickel alloy used in the electronics industry. A particular alloy with a density of 8.70 g/cm3 and containing 0.024% silicon by mass is used to make a rectangular plate that is 30.0 cm long, 17.0 cm wide and 3.00 mm thick. What is the volume of the alloy? What is the mass of the alloy? What is the mass of just the silicon in the sample?
Chapter 1
Chemistry 1A
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Practice Problems: (ANSWERS) 1. 2.
3.441 x 10-22 g a) 0.000343 km b) 645,000,000 ml
3.
0.457 quarts/year.
4.
a) 217 Kelvin
3.43 x 10-4km 6.45 x.108 ml
b) -69 ˚F 5.
3.900 g; answer has 4 significant figures
6.
0.743 g/ml
7.
Precision (measurements agree with each other). Accuracy (measurement agrees with true value). You may want to check the weight of a suitcase so you will not be charged extra for too much baggage before going on an airline flight. You may weigh your suitcase on the same bathroom scale several times and find the numbers agree with each other (precision). If the bathroom scale always reads 5 pounds lighter that the true value you will not be accurate and possible pay the extra fee. That bathroom scale has a systematic error that may be fixed with calibration.
8.
9.
10.
C
The reaction with zinc and hydrochloric acid to produce a gas
P
Crystallization of CuSO4 by evaporation of its aqueous solution
P
Metals are shiny, malleable, ductile, good conductors of heat and electricity
C
Alkali metals combine with halogens in a 1:1 ratio to form a compound
a) b)
Oxygen, O2 Sodium bromide, NaBr
a, b, d, e, i a, b, c, j,
c)
Cu-Zn alloy called brass a, f, k
d)
Burrito
a, g
e)
Potassium
a, b, e, h
f)
Hypothesis
n
a) 153 cm3 volume b) 1330 g mass alloy c) 0.32 g mass of just the silicon
