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Chem 109
Exam #1 (Norton 1, 2, 3)
112
Chemistry
Undergraduate 1
02/01/2012

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Term
Matter
Definition
Everything in the universe that has mass and occupies space
Term
Energy
Definition
Capacity to transfer heat or do work
Term
Chemistry
Definition
The study of the composition, structure, and properties of matter
Term
Substance
Definition
Matter that cannot be broken down to simpler matter by any physical process; also known as a “pure substance”
Term
Physical Process (Substances)
Definition
Transformation of a sample of matter, such as a change in its physical state, that does not alter the chemical identity of any substance in the sample
Term
Mixture
Definition
Combination of pure substances in variable proportions in which the individual substances retain their chemical identities and can be separated from one another by a physical process
Term
Homogeneous Mix
Definition
Mixture components uniformly distributed throughout
Term
Solution (Homo Mix)
Definition
Another name for a homogenous mixture, often a liquid
Term
Heterogeneous Mix
Definition
Mixture components are not distributed uniformly, containing distinct regions
Term
Compound
Definition
Pure substance that is composed of two or more elements linked together in fixed proportions and that can be broken down to those elements by some chemical process
Term
Element
Definition
Pure substance that cannot be separated into simpler substances by any chemical process
Term
Atom
Definition
The smallest particle of an element that retains the chemical characteristics of the element
Term
Molecule
Definition
A collection of atoms chemically bonded together in characteristic proportions
Term
Chemical Formula
Definition
A notation for representing elements and compounds; consists of the symbols of the constituent elements and subscripts identifying the number of atoms of each element
Term
Chemical Equation
Definition
Notation in which chemical formulas express the identities and their coefficients express the quantities of substances involved in a chemical reaction
Term
Chemical Bond
Definition
The energy that holds two atoms in a molecule together
Term
Filtration
Definition
A process for separating particles suspended in a liquid or a gas from that liquid or gas by passing the mixture through a medium that retains the particles
Term
Solvent Extraction (Filtration)
Definition
Used to further filter particles by soaking the filter in a vial of solvent that dissolves many of the compounds present inside the phytoplankton cells
Term
Thin Layer Chromatography (TLC)
Definition
A small volume of pigment extract is applied to the porous surface coating a thin plate, then the edge of the plate nearest the sample is immersed in a shallow bath of solvent, the solvent is drawn up the face of the plate by capillary action
Term
Distillation
Definition
A separation technique in which the more volatile components of a mixture are vaporized and then condensed, thereby separating them from the less volatile components
Term
Intensive Properties
Definition
A property that is independent of the amount of substance present (Pure Substances)
Term
Extensive Properties
Definition
A property that varies with the quantity of the substance present
Term
Physical Properties
Definition
A property of a substance that can be observed without changing it into another substance
Term
Density
Definition
The ratio of the mass (m) of an object to its volume (V)
Term
Chemical Property
Definition
A property of a substance that can be observed only by reacting it to form another substance
Term
Scientific Method
Definition
An approach to acquiring knowledge based on observation of phenomena, development of a testable hypothesis, and additional experiments that test the validity of the hypothesis
Term
Hypothesis
Definition
A tentative and testable explanation for an observation or a series of observations
Term
Scientific Theory (model)
Definition
A general explanation of a widely observed phenomenon that has been extensively tested and validated
Term
e = mc^2
Definition
Energy (e) is equal to the equivalent of the mass of matter (m) times the speed of light (c) squared
Term
Henri Lemaitre
Definition
Proposed the “Big Bang” in 1927
Term
Sir Fred Hoyle
Definition
Coined the term “Big Bang”
Term
Robert Dicke
Definition
Predicted the cosmic microwave radiation of the universe
Term
Meter
Definition
Predicted the cosmic microwave radiation of the universe
Term
Significant Figures (Sig Figs)
Definition
All the certain digits in a measured value plus one estimated digit. The greater the number of significant figures, the greater the certainty with which the value is known
Term
Addition & Subtraction of Sig Figs
Definition
The decimal position of the least significant digit is the weakest link and it determines the significant figures in the final answer
Term
Multiplying & Dividing of Sig Figs
Definition
The significant figures of the answer are determined by the value with the fewest significant digits
Term
Precision
Definition
The extent to which repeated measurements of the same variable agree
Term
Accuracy
Definition
Agreement between an experimental value and the true value
Term
Conversion Factors
Definition
A fraction in which the numerator is equivalent to the denominator but is expressed in different units, making the value of the fraction one
Term
Conversion Factor Examples
Definition
o 1 ft = .3048 m
o 1 km = .6214 mi
o C* = 5/9 (F* - 32)
Term
Kelvin (K)
Definition
The SI unit of temperature
Term
Absolute Zero (0 K)
Definition
The zero point on the Kelvin temperature scale; theoretically the lowest temperature possible
Term
Law of Constant Composition
Definition
All samples of a particular compound contain the same elements combined in the same proportions
Term
Chemical Bond
Definition
The energy that holds two atoms in a molecule together
Term
Wilson & Penzias
Definition
Received Nobel Prize in 1978 for actually discovering (in 1965) cosmic microwave radiation
Term
Quarks
Definition
Tiny particles that initially condensed into neutrons. Neutrons with a half-life of 12 minutes began to decay into equal amounts of protons and electrons; come in 3 categories called "colors" (blue, green, red) for each color their are 6 "flavors" (up, down, strange, charmed, bottom, and top); are held together through the actions of particles called "gluons"
Term
Subatomic Particles
Definition
The neutrons, protons, and electrons in an atom.
In part discovered by J.J. Thomson as he determined the mass-to-charge-ratio (m/e) of electrons
Term
Cathode Rays
Definition
Streams of electrons emitted by the cathode in a partially evacuated tube; used by J.J. Thomson to discover electrodes
Term
Nucleo-Synthesis
Definition
Formation of the nuclei of elements in the early moments of the universe and later in the core of giant stars
Term
Electrons
Definition
Subatomic particle that has a negative charge and essentially zero mass
Term
Radioactivity
Definition
Spontaneous emission of high – energy radiation and particles by materials; discovered by Ernest Rutherford
Term
Beta (B) Particles
Definition
A radioactive emission that is a high-energy electron
Term
Alpha (a) Particles
Definition
A radioactive emission with a charge of 2+ and a mass equivalent to that of a helium nucleus
Term
Robert Milikan
Definition
In 1909 determined the charge of electrons, allowing him to discover the mass
Term
V0 (Terminal Velocity) (Milikan)
Definition
-k (constant based on air resistance) x m (mass of the drop) x g (acceleration due to gravity); Velocity is related to charge thru: v1 = k(Eq - mg); e1 = charge of an electron
Term
Nucleus
Definition
The positively charged center of an atom that contains nearly all the atom’s mass; Hans Geiger and Ernest Mardsen, students of Rutherford, discovered the current understanding of atomic structure and dismissed the plum-pudding model
Term
Protons
Definition
A positively charged subatomic particle present in the nucleus of an atom
Term
Neutrons
Definition
An electrically neutral subatomic particle found in the nucleus of an atom; Another of Rutherford's student, James Chadwick discovered and isolated neutrons
Term
Atomic Mass Units (amu)
Definition
Unit used to express the relative masses of atoms and subatomic particles that is exactly 1/12 the mass of one atom of carbon with 6 protons and 6 neutrons in its nucleus;
Term
Daltons (Da)
Definition
A unit of mass identical to 1 atomic mass unit, also known as a unified atomic mass unit (u)
Term
Ernest Rutherford
Definition
Debunked the “plum-pudding” model of an atom in 1907, leading to the discovery of the atomic nucleus
Term
Rutherford Backscattering Spectrometry
Definition
Analytic technique using a beam of high-energy ions is directed at the sample of interest, most of the ions implant into the sample, but some of the ions will bounce back off of the sample (backscatter) due to interaction with the atomic nuclei in the sample. The number of backscattered ions can be used to find the square of the atomic number and thus, the identity of the target element. RBS is often used to measure the stoichiometry, or ratio of one element to another, of thin films; Something small, dense, and positively charged within the atoms caused the alpha particles to be repelled, it was the nucleus
Term
# of Sub Atomic Particles
Definition
There are more than 40 sub-atomic particles, but none as important as the proton, neutron, and electron
Term
Ions
Definition
An atom or group of atoms that has a positive or negative charge; Discovered by one of Thomson’s students, Francis W. Aston while using a positive-ray analyzer. Aston disproved John Dalton in that elements could have different masses
Term
Isotopes
Definition
Atoms of an element containing the same number of protons but different number of neutrons
Term
Nuclides
Definition
A specific isotope of an element
Term
Atomic Number (z)
Definition
The number of protons in an atom
Term
Nucleon
Definition
Either a proton or neutron in a nucleus
Term
Mass Number (A)
Definition
The number of nucleons in an atom
Term
Periodic Table of the Elements
Definition
- A chart of the elements in order of their atomic numbers, and in a pattern based on their physical and chemical properties
Term
Average Atomic Mass
Definition
A weighted average of masses of all isotopes of an element, calculated by multiplying the natural abundance of each isotope by its mass in atomic mass units and then summing these products
Term
Natural Abudnance
Definition
- The proportion of a particular isotope usually expressed as a percentage, relative to all the isotopes of that element in a natural sample
Term
Dimitri Mendeleev
Definition
Published the forerunner to the modern periodic table in 1872.
Term
Periods
Definition
The horizontal rows in the periodic table
Term
Group (family)
Definition
All the elements in the same column of the periodic table
Term
Halogen
Definition
An element in group 17 of the periodic table: "salt former"
Term
Alkali Metal
Definition
An element in group 1 of the periodic table
Term
Lanthanides
Definition
Elements in the row with atomic numbers from 58 to 71
Term
Actinides
Definition
Elements in the row with atomic numbers from 80 to 103; Most of the nuclides are radioactive, and none of those with the atomic number above 94 occur in nature
Term
Alkaline Earth Metals
Definition
An element in group 2 of the periodic table
Term
Metals
Definition
The elements on the left side of the periodic table that are typically shiny solids that conduct heat and electricity well and are malleable and ductile
Term
Non-Metals
Definition
Elements with properties opposite those of metals including poor conductivity of heat and electricity
Term
Metalloids and Semimetals
Definition
Elements along the border of the periodic table between metals and nonmetals; they have some metallic and some nonmetallic properties
Term
Main Group Elements (Representative Elements)
Definition
The elements in groups 1, 2, and 13-18 of the periodic table; Include the most abundant elements in the solar system and many of the most abundant on Earth
Term
Transition Metals
Definition
The elements in groups 3-12 of the periodic table; Nearly all classic metals
Term
Noble Gasses
Definition
The elements in group 18 of the periodic table; Chemically unreactive, therefore elusive for early chemist; Missing on Mendeleev's table, as the first (Helium) was not discovered until 1895
Term
Dalton's Law of Multiple Proportions
Definition
The ratio of the two masses of one element that react with a given mass of another element to form two different compounds is the ratio of two small whole numbers
Term
Molecular Compound
Definition
A compound composed of atoms held together in molecules by covalent bonds
Term
Covalent Compound
Definition
A bond between two atoms created by sharing one or more pairs of electrons
Term
Molecular Formula
Definition
A notation showing the number and type of atoms present in one molecule of a molecular compound
Term
Ionic Compound
Definition
A compound composed of positively and negatively charged ions held together by electrostatic attraction; Each contains a metallic element combined with a nonmetal
Term
Cation
Definition
Positively charged particle created when an atom or molecule loses one or more electrons; Atoms shrink when they lose an electron and expand when they gain one
Term
Monatomic Ions
Definition
Single atoms with a positive/negative charge that form compounds
Term
Anion
Definition
Negatively charged particle created when an atom or molecule gains one or more electrons
Term
Empirical Formula
Definition
A formula showing the smallest whole-number ratio of elements in a compound
Term
Formula Unit
Definition
The smallest electrically neutral unit of an ionic compound
Term
Naming a Binary Ionic Compound
Definition
Start with the name of the cation, then add the name of the anion and change its ending to “ide”; Electrically neutral; Magnesium fluoride can only mean MgF2
Term
Naming Binary Compounds of Transition Metals
Definition
Use roman numerals to indicate the charge of the element, or “ous” to indicate the ion with the lower charge and “ic” to indicate the ion with the higher charge
Term
Polyatomic Ions
Definition
Charged groups of two or more atoms joined together by covalent bonds
Term
Ammonium
Definition
NH4+, the only polyatomic cation; all others are anions
Term
Oxoanions
Definition
Polyatomic ions that contain oxygen in combination with one or more other elements;  Names are usually based on the element that appears first in the formula, with the ending changed to either “ite” (lesser) or “ate” (greater) based on the # of oxygen atoms;  Oxoanions with the largest number of oxygen atoms has the prefix “per” and that with the smallest has the prefix “hypo”
Term
Acids
Definition
Compounds that release hydrogen ions (H+) when theAcids- Compounds that release hydrogen ions (H+) when they dissolve in water; their chemical formulas begin with H
Term
Naming Acids
Definition
Affix the prefix “hydro” to the name of the element other than hydrogen, then replace the last syllable with “ic” and end with adding “acid”
Term
Carboxylic Acids
Definition
An organic compound containing the –COOH functional group; Ionization of the hydrogen atom is the source of acidity in these compounds
Term
Functional Group
Definition
A structural subunit in organic molecules that imparts characteristic chemical and physical properties
Term
Organic Compound
Definition
Compounds containing carbon, and commonly including certain other elements such as hydrogen, oxygen, and nitrogen
Term
Hydrogen & Helium
Definition
Two of the most abundant elements in the universe
Term
(Primordial) Nucleosynthesis
Definition
The natural formation of nuclei as a result of fusion and other nuclear processes
Term
Element Composition of the Early Universe
Definition
75% hydrogen, 25% helium for millions of years (it was too cold)
Term
Carbon-12
Definition
Initially created in the core of red giant stars through a “triple-alpha process” producing a nucleus with 6 p and 6 n; Carbon would then become the building block of Oxygen-16, Neon-20, and Magnesium-24
Term
Neutron Capture
Definition
The absorption of a neutron by a nucleus
Term
Beta (B) Decy
Definition
The process by which a neutron decays into a proton and beta particle (0/-1 B)
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