Download Unit 1 Tro Textbook Enlow`s Brief: Chapter 1: Matter, Measurement

Unit 1 Tro Textbook Enlow’s Brief:
Chapter 1: Matter, Measurement, and Problem Solving
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Properties of matter are determined by the properties of atoms and molecules
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Hypotheses are falsifiable
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Laws describe how matter behaves
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Theories explain how matter behaves and why
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Separation of mixtures utilizes the fact that substances within the mixtures have different physical
or chemical properties (decant, distill, filter)
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General rule of changes: Just changes the appearance and not the composition = physical
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Phy property – property displayed without changing its composition (odor, taste, color, appearance,
mp, bp, fp, density)
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Chem property – property displayed only by changing composition during chemical reaction
(corrosiveness, acidity, toxicity, flammability, etc)
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Energy is a fundamental part of physical or chemical changes (exo or endothermic processes)
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energy and work
Total Energy = kinetic energy(E of motion) + potential energy (E of position or composition)
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Chemical potential energy is the energy contained within molecules and it arises primarily from
the electrostatic forces between the electrically charged particles (protons and neutrons)
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Kinetic energy can be converted to thermal energy in collision, which causes the temp of atoms to
rise
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Law of conservation of energy
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Tendency of systems with high PE to change in a way to lower the PE (go from unstable to stable)
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Temperature – a measure of the average KE of the atoms (it’s a measure of molecular motion) ; it
determines the direction of thermal energy transfer (always from hotter to colder systems) ; Kelvin
is the absolute temperature scale and does not utilize negative #s
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Measurement – scientific measurments are reported so that every digit is certain except for the last
one which is estimated
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Error – either random or systematic
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Sig Figs
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the more SFs, the more certain of the msmt
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Any leading zeros do not add to the certainty, just the scale of the msmt
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There are NO LIMITED SFs in EXACT MEASUREMENTS!!!! Imagine there are unlimited zeros after
the decimal! DO NOT COUNTY SFs here!!!
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Ex: 2 atoms of oxygen per molecule of carbon dioxide (this is 2.00000…..)
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Ex: metric system (100 cm per meter)
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Integral #s in equations (constants and formulas!)
Chapter 2: Atoms and Elements
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Scanning Tunneling Microscopy – can image atoms, nanotechnology uses this tech
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Law of Conservation of Mass (Lavosier)
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Law of Definite Proportions – ratio is constant (Proust)
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Law of Multiple Proportions – ratio of small whole numbers but can vary (Dalton)
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JJ Thomson - Cathode ray , partially evacuated glass tubes with two electrodes, increase the
voltage between the electrodes and beam made of electrons traveled from the cathode to the
anode, determined charge per gram of electron
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Milikan – oil drop exp, charge of a single electron, determined that each oil drop must have an
integral # of electrons so there had to be a fundamental charge
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Rutherford – gold foil, radioactivity, deflection, nuclear theory (most of mass and all positive
charge of atom is in small core called nucleus, most of vol of atom is empty space where tiny eare dispersed, electrically neutral bc equal amounts of e- and p+)
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Chadwick – neutron
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Amu, the charge of the e- and p+ are equal in magnitude but opposite in charge
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The # of p+ define the element, the # of e- define the reactivity
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Isotopes and natural abundance = determines the average atomic mass
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A # = mass #
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Mass Spec graphs – must normalize the percent abundance
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Analogies of how many particles are in a mole – IT’S AMAZING!!!
Z # = atomic #
Chapter 3: Molecules, Compounds, and Chemical Equations
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Bonds – Covalent bonds are very stable because of the positioning of the electrons between the
positively charged nuclei of the atoms (the lowest possible potential energy makes it the most
stable!)
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Empirical formulas – relative number of atoms
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Molecular formula – actual number of atoms
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Structural formula – lines represent where the covalent bonds are between atoms
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Models - ball and stick model, space filling model
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Atomic elements
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Molecular elements – exist diatomically, polyatomic molecules (P4 and S8)
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Molecular compounds vs ionic compounds/formula units
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Hydrates contain a specific number of water molecules associated with each formula unit (waters
of hydration)
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Oxyacids – contain hydrogen and oxyanion (like chlorate) from the polyatomic ions – naming ate to
ic and ite to ous
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Mass Percent can be used as a conversion factor
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Chemical formula always gives a relationship between amounts in moles of substances not in
masses of substances
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Organic vs Inorganic – ex: cinnamonaldehyde
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Hydrocarbons (fuels) and Functionalized hydrocarbonds (alcohols, etc)
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Organic prefixes
Chapter 4: Chemical Quantities and Aqueous Reactions (4.1-4.3)
Stoichiometry – limiting reactant limits the amount of product that is produced