148 terms

Chem 1 Final Vocab

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Matter
that which has mass and occupies space
Crystal lattice
a repeating three-dimensional pattern of ions
Translational motion
Motion from one point to another which does not involve repeatedly passing the same point in space
Rotational motion
Motion when an object moves aroud its centre of mass
Vibrational motion
atoms in the molecule move periodically toward and away from one another
Fluid
any substance that can flow
Compressible
can be made to occupy a smaller volume
Density
the amount of matter in a given space, mass/volume
Temperature
the average kinetic energy of the individual particles
Maxwell-Boltzman distribution
An increase in temp spreads out the distribution and the mean speed shifts upward
Absolute Zero
The coldest temperature, 0 Kelvin, that can be reached. It is the hypothetical temperature at which all molecular motion stops.
Kelvin
SI unit for temperature
Condensation
gas to liquid
Evaporation
Liquid to Gas, the process by which water changes from liquid form to an atmospheric gas
Vaporization
liquid to gas
Sublimation
solid to gas
Deposition
gas to solid
Endothermic
describes a process in which heat is absorbed from the environment
Exothermic
chemical reaction in which energy is primarily given off in the form of heat
Kinetic Energy
the energy an object has due to its motion
Potential energy
energy stored due to an object's position or arrangement
Phase Change
the reversible physical change that occurs when a substance changes from one state of matter to another
Physical Change
a change in a substance that does not involve a change in the identity of the substance
Boiling point
The temperature at which a liquid boils
Melting/Freezing point
the temperature at which a substance changes from a solid to a liquid or a liquid to a solid
Heating/cooling curve
graph showing the increase of temp and energy for a substance
Pure substance
a sample of matter, either a single element or a single compound, that has definite chemical and physical properties
Mixture
a substance consisting of two or more substances mixed together (not in fixed proportions and not with chemical bonding)
Scientific law
a concise statement that summarizes the results of many observations and experiments
Scientific Theory
a well-tested concept that explains a wide range of observations
Pressure
the force applied to a unit area of surface
Torr(mmHg)
Ways to measure pressure. One atmosphere = 760 torr or mmHg
Atmosphere
A type of unit to measure pressure
Directly proportional
a term used to describe the relationship between two variables whose graph is a straight line passing through the point (0,0)
Inversely proportional
a term used to describe the relationship between two variables whose product is constant
Boyle's Law
The relationship between the pressure and volume of a gas at constant temperture; when volume increase, pressure decreases, P1V1=P2V2
Charles' Law
the law that states that for a fixed amount of gas at a constant pressure, the volume of the gas increases as the temperature of the gas increases and the volume of the gas decreases as the temperature of the gas decreases, V1/T1=V2/T2
Kinetic Theory of Gasses
The model states that the movement of molecules in a gas is random and that no energy is lost when they collide with each other or their surroundings.
Elastic collisions
encounters between gas particles in which kinetic energy is transferred without loss from one particle to another
Cathode Ray
a beam of electrons emitted by the cathode of an electrical discharge tube
Subatomic Particles
protons, neutrons, and electrons
Atomic Number
the number of protons in the nucleus of an atom
Mass Number
the sum of the numbers of protons and neutrons in the nucleus of an atom
Atomic Mass
total mass of the protons and neutrons in an atom, measured in atomic mass units
Isotope
atoms of the same element that have different numbers of neutrons
Frequency
The number of waves that have passed through a specific point in a certain amount of time units.
Wavelength
The distance between crests of waves, such as those of the electromagnetic spectrum.
Photon
a tiny particle or packet of light energy
Electromagnetic Spectrum
arrangement of electromagnetic radiation--including radio waves, visible light from the Sun, gamma rays, X rays, ultraviolet waves, infrared waves, and microwaves--according to their wavelengths
Radiation
energy that is radiated or transmitted in the form of rays or waves or particles
Quantization
process of measuring the amplitude or energy of each sample at that point in the waveform-also increases dynamic range
Line Emission Spectra
when light from excited atoms of an element is passed through a prism, distinct colored lines are produced which can be used to identify the element.
Energy Level
a region of an atom in which electrons of the same energy are likely to be found
Sublevel
One part of a level, each of which can hold different numbers of electrons
Orbital
a region in an atom where there is a high probability of finding electrons
Electron Configuration
the ways in which electrons are arranged in various orbitals around the nuclei of atoms
Uncertainty Principle
The idea that we do know no anything for certain and all we know is possibilities, probabilities, and tendencies. Put forth by German physicist Heisenberg.
Pauli Exclusion Principle
no two electrons in the same atom can have the same set of four quantum numbers
Absorption
The Process of when and atom takes in Light and converts it into energy. Opposite of Reflection
Emission
something sent out; putting into circulation
J.J Thomson's Model
Thomson's model described the atom as a positively charged sphere, in which negatively charged particles were scattered. (Like raisins in bread pudding.)
Dalton's Model
described atoms as the smallest particle of matter ; indivisible; developed the Atomic Theory
Rutherford's Model
atoms possitively charged particles were contained in the nucleus, the negatively charged electrons were scattered outside the nucleus around the edge
Bohr Model
model of the atom in which electrons move rapidly around the nucleus in paths called orbits
Quantum Mechanical Model
determines the allowed energies an electron can have and how likely it is to find the electron in various locations around the nucleus
Ground State
the lowest energy state of an atom
Excited State
a state in which an atom has a higher potential energy than it has in its ground state
Excitation
The process of an electron jumping to a higher energy level in its atom.
Relaxation
The process of an electron coming back to its original energy level in its atom.
Ion
atom that has a positive or negative charge
Cation
a positively charged ion
Anion
a negatively charged ion
Ionic bond
a chemical bond in which one atom loses an electron to form a positive ion and the other atom gains to electron to form a negative ion
Crystal Lattice
a 3-dimensional geometric arrangement of the atoms or molecules or ions composing a crystal
Atomic Radius
one-half the distance between the nuclei of identical atoms that are bonded together
Ionization Energy
the amount of energy required to remove an electron from an atom
Ionic Radius
Distance from the center of an ion's nucleus to its outermost electron
Ionic compound
a compound that consists of positive and negative ions
Binary Compound
chemical compound composed of only two elements
Formula Unit
the lowest whole-number ratio of ions in an ionic compound
Octet rule
States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons
isoelectronic
having the same number of electrons
Coulomb's Law
electric force between charged objects depends on the distance between the objects and the magnitude of the charges.
Shielding
The more electrons there are to hold on to, the more the strength of the nucleus gets diffused
Mole
the SI base unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12 g of carbon-12
Avogadro's Number
number of representative particles in a mole, 6.02 X 10^23
Molar Mass
the mass of one mole of a pure substance
Covalent Bond
a chemical bond that involves sharing a pair of electrons between atoms in a molecule
Lone pair
Pair of electrons associated with one atom in a molecule and not involved in bonding.
Molecule
two or more atoms held together by covalent bonds
Polyatomic Ion
a charged group of covalently bonded atoms
Covalent Compound
a chemical compound formed by the sharing of electrons
Lewis Structure
a structural formula in which electrons are represented by dots; dot pairs or dashes between two atomic symbols represent pairs in covalent bonds.
VSEPR model
Valence Shell Electron Pair Repulsion model, which is based on an arrangement that minimizes the repulsion of shared and unshared pairs of electrons around the central atom
Electron Geometry
the arrangement of electron domains about the central atom
Electron regions
electron cloud, the area of possibilities in which the electrons could be in a general region.
Bond Angle
the angle formed by two bonds to the same atoms
Electronegativity
a measure of the ability of an atom in a chemical compound to attract electrons
Polar covalent bond
a covalent bond in which electrons are not shared equally
non-polar covalent bond
A covalent bond in which the bonding electrons are shared equally by the bonded atoms, resulting in a balanced distribution of electrical charge
Bond Dipole
an indicator in a Lewis structure that shows which element is more electronegative
Lone Pair Dipole
no bond, just a lone pair, unshared
Symmetric Dipoles
there are equal forces on each side that cancel each other out, no net dipole because they fully cancel
Net dipole
the overall direction of partial negative charge in a molecule
Molecular Polarity
the uneven distribution of molecular charge
Polar Molecule
molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end
Intermolecular Forces
forces of attraction between molecules. The following types are: London Dispersion Forces, Dipole-Dipole Forces, and Hydrogen Bonds
Dipole-Dipole Forces
attractions between oppositely charged regions of polar molecules
Hydrogen Bonds
attractive forces in which a hydrogen covalently bonded to a very electronegative atom is also weakly bonded to an unshared electron pair of another electronegative atom
London Dispersion Forces
the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles
Temporary Dipole
An atom or molecule in which the spatial center of positive charge is momentarily different from the center of negative charge.
Percent Composition
the percent by mass of each element in a compound
Empirical Formula
a formula showing the lowest whole number ratio of atoms in a compound
Solution
A homogeneous mixture of two or more substances
Solute
the dissolved substance in a solution
Solvent
the substance in which the solute dissolves
Dissolving
the process of going into solution
Ion-Dipole Bonding
Attraction between an ion and a dipolar molecule
Homogeneous Mixture
a mixture in which substances are evenly distributed throughout the mixture
Heterogeneous Mixture
a mixture in which different materials can be distinguished easily
Saturated
being the most concentrated solution possible at a given temperature
Unsaturated
solution in which it is possible for more solute to be dissolved
Concentrated
a solution containing relatively large amounts of solute
Dilute
make (a liquid) less concentrated; reduce in strength; Ex. dilute the influence of the president
Soluble
capable of being dissolved
Insoluble
not able to dissolve
Electrical Conductivity
how well a substance allows electricity to flow through it.
Hydration Energy
the attraction between ions and water in the solution; the change in energy when gaseous ions dissolve in water
Lattice Energy
the energy released when one mole of an ionic crystalline compound is formed from gaseous ions
Entropy
a measure of the disorder of a system
Dynamic Equilibrium
result of diffusion where there is continuous movement of particles but no overall change in concentration
Concentration
the strength of a solution
Molarity
concentration measured by the number of moles of solute per liter of solvent
Dilution
the process of adding solvent to lower the concentration of solute in a solution
Volumetric Flask
used to make solutions of known concentration, accurate liq. vol. measurement
Graduated Pipet
Used to deliver precise volumes of liquids
Organic Molecule
carbon-based molecule
Structural Formula
an expanded molecular formula showing the arrangement of atoms within the molecule
Line-Angle Drawing
zig zag format of how many bonds are in the molecule
double lines for double bonds etc. and draw in the bond angles for each one
HydroCarbon
an organic compound containing only carbon and hydrogen
Functional Group
the portion of a molecule that is active in a chemical reaction and that determines the properties of many organic compounds
Alcohol
-ol
Amine
-Amine, -Amino, -ine
Carboxylic Acid
-(o)ic Acid
Ester
-Oate
Amide
-Amide
Metallic Bonding
the chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons
Covalent Network
this solid consists of atoms held together throughout the entire sample of material in large networks or chains by covalent bonds, and has a high melting point