Shared Flashcard Set

Details

Chemistry 112
Lane Commuinty College
145
Chemistry
Undergraduate 1
04/25/2011

Additional Chemistry Flashcards

 


 

Cards

Term
Term
Definition
Definition
Term
Chemistry
Definition
The study of matter
Term
Matter
Definition
Anything that has mass and volume
Term
Mass
Definition
A measure of the gravitational force acting on an object
Term
Weight
Definition
A measure of the mass of an object on Earth
Term
Physical Properties
Definition
Properties that can be observed or measured without changing the composition of the matter
Term
Chemical Properties
Definition
Properties observed when one attempts to change matter into some other type of matter
Term
Chemical Composition
Definition
What chemicals are present
Term
Chemical Reactivity
Definition
The ability to interact with other chemicals
Term
Physical Change
Definition
A change in the state of matter (does not alter the chemical makeup)
Term
Chemical Change
Definition
Substance changes into something new
Term
States of Matter
Definition
Solid, Liquid, Gas
Term
Change of State
Definition
Conversion of matter from one state to another
Term
Pure Substance
Definition
Matter that is uniform in its chemical composition and properties
Term
Mixture
Definition
A blend of two or more pure substances in any ratio, each retaining their identity
Term
Element
Definition
Pure substance that cannot be broken down chemically into simpler substances
Term
Chemical Compounds
Definition
Two or more elements combined chemically in specific ratios to form a pure substance
Term
Atom
Definition
A single molecule of an element
Term
Molecule
Definition
Two or more elements combined chemically in specific ratios to form a pure substance
Term
Chemical Formula
Definition
A notation for a chemical compound using symbols and subscripts to show how many atoms of each element are present
Term
Physical quantities
Definition
Measurements of physical properties such as height, volume and temperature requiring both a number and a unit
Term
SI Units
Definition
Scientific standard set of units closely related to metric units
Term
Atomic Theory 1
Definition
All matter is composed of atoms
Term
Atomic Theory 2
Definition
The atoms of a given element differ from the atoms of all other elements
Term
Atomic Theory 3
Definition
Chemical compounds consist of atoms combined in specific ratios
Term
Atomic Theory 4
Definition
Chemical reactions change only the way the atoms are combined in compounds; the atoms themselves are unchanged
Term
Proton
Definition
Subatomic particle with a positive charge
Term
Electron
Definition
Subatomic particle with a negative charge
Term
Neutron
Definition
Subatomic particle with no charge
Term
Nuclear strong force
Definition
The force holding protons and neutrons together in an atom’s nucleus
Term
Mesons
Definition
Exchanged between protons and neutrons creating nuclear strong force
Term
Atomic number
Definition
(Z) – The number of protons in each atom of an element
Term
Mass Number
Definition
(A)– The total number of protons and neutrons in a atom
Term
Isotopes
Definition
Atoms with identical atomic numbers (Z) but different mass numbers (A); same number of protons, but varying number of neutrons
Term
Atomic Weight
Definition
Average mass of an element and all of its naturally occurring isotopes
Term
Periodic Law
Definition
When all the elements are placed in order of increasing atomic number, elements with similar chemical properties will occur at regular (periodic) intervals.
Term
Periods
Definition
Seven horizontal rows of the periodic table
Term
Groups
Definition
18 vertical columns of the periodic table
Term
Main Groups
Definition
The two groups on the far left (1&2) and the six on the far right (13-18)
Term
Transition Metal Groups
Definition
Elements in groups 3-12
Term
Inner Transition Metal Groups
Definition
The 14 unnumbered groups shown at the bottom of the table
Term
Alkali metals
Definition
Group 1 elements
Term
Alkaline earth metals
Definition
Group 2 elements
Term
Halogens
Definition
Group 7 elements
Term
Nobel Gases
Definition
Group 8 elements
Term
Valence Electrons
Definition
Electrons in the outermost shell of an atom
Term
Distinguishing Electron
Definition
The last electron added to an element
Term
Electrically neutral
Definition
All atoms of elements in the periodic table are this because they contain equal numbers of protons and electrons.
Term
Cation
Definition
A positively charged ion due to the loss of one or more electrons
Term
Anion
Definition
A negatively charged ion due to the gain of one or more electrons
Term
Ion
Definition
An atom that has gained or lost one or more electrons and now has a charge
Term
Ionization energy
Definition
The energy required to remove one electron from a single atom in the gaseous state
Term
Electron affinity
Definition
The energy released on adding an electron to a single atom in the gaseous state
Term
First ionization energy
Definition
The amount of energy required to remove the first electron from an atom
Term
Second ionization energy
Definition
The amount of energy required to remove the second electron from an atom
Term
Ionic bond
Definition
The electrical attractions between ions of opposite charge in a crystal
Term
Ionic compound
Definition
A compound that contains ionic bonds
Term
Octet Rule
Definition
After bonding, each atom will have 8 electrons in its valence shell
Term
Crystal lattice
Definition
The most stable form of an ionic compound, a crystal of many ions in a rigid, three-dimensional arrangement
Term
Ionic solids
Definition
Individual cation/anion bonds cannot be determined, therefore, collectively called this
Term
Polyatomic ions
Definition
Ions that are composed of more than one atom
Term
Molecular weight
Definition
The sum of the atomic weights for all the atoms in the molecule; the average mass of a substance’s molecules
Term
Formula weight
Definition
The sum of the atomic weights for all the ions in the compound
Term
Covalent bond
Definition
The bond formed when atoms share electrons
Term
Molecule
Definition
A group of atoms held together by covalent bonds
Term
Repulsive interaction
Definition
Like-charged atomic particles repel each other – nuclei and electrons
Term
Attractive interaction
Definition
Oppositely charged atomic particles attract each other nucleus/electrons
Term
Single bond
Definition
A covalent bond formed by sharing one electron pair
Term
Double bond
Definition
A covalent bond formed by sharing two electron pairs
Term
Triple bond
Definition
A covalent bond formed by sharing threre electron pairs
Term
Diatomic
Definition
Two-atom molecules (H2, Cl2, N2, O2, F2, Br2, I2)
Term
Coordinate Covalent Bonds
Definition
The covalent bond that forms when both electrons are donated by the same atom. This creates a charged molecule
Term
Molecular formula
Definition
A formula that shows the numbers and kinds of atoms in one molecule of a molecular compound H2O
Term
Formula Unit
Definition
The formula that identifies the smallest neutral unit in an ionic compound NaCl
Term
Structural formula
Definition
A molecular representation that shows the connections among atoms by using lines to represent covalent bonds. H-O-H
Term
Polar covalent bonds
Definition
In molecules of different elements, electrons are attracted more strongly by one atom that by the other and thus are shared unequally.
Term
Electronegativity
Definition
The ability of an atom to attract electrons in a covalent bond
Term
Electronegativity difference <0.5
Definition
Covalent bonds
Term
Electronegativity difference >0.5 & <2.0
Definition
Increasingly polar covalent bonds
Term
Electronetativity difference > 2.0
Definition
Increasingly ionic bonds
Term
Intermolecular Forces
Definition
Weak bonds that form between molecules (other than ionic and covalent)
Term
Dipole-dipole
Definition
An intermolecular force where positive and negative ends of polar molecules are attracted to each other. This results in higher boiling points
Term
London dispersion forces
Definition
Averaged over time, electron dispersion is uniform. A snap-shot in time may reveal more polarity of electrons and thus a momentary polarity to the molecule
Term
Reactant
Definition
A substance that undergoes change in a chemical reaction and is written on the left side of the reaction arrow in a chemical equation
Term
Product
Definition
A substance that is formed in a chemical reaction and is written on the right side of the reaction arrow in a chemical equation
Term
Law of Conservation of Mass
Definition
Matter is neither created nor destroyed in chemical reactions.
Term
Combination/Addition reaction
Definition
Molecules A and B combine/react to make C (A+B->C)
Term
Decomposition Reaction
Definition
Molecule A breaks down into molecules B & C (A->B+C)
Term
Single Replacement
Definition
One molecule replaces another (A+BC->AC+B)
Term
Double Replacement
Definition
Both molecules break down and form new molecules (AB+CD->AC+BD)
Term
Mole
Definition
The amount whose mass in grams is numerically equal to its molecular or formula weight
Term
Avogadro’s Number
Definition
The number of molecules or formula units in a mole Na = 6.022 x 1023
Term
Potential energy
Definition
Stored energy ie a coiled spring
Term
Kinetic energy
Definition
Energy in motion ie hands of the clock moving
Term
Bond dissociation energy
Definition
The amount of energy that must be supplied to break a bond and separate the atoms in an isolated gaseous molecule
Term
Law of Conservation of energy
Definition
Energy can be neither created nor destroyed in any physical or chemical change
Term
Heat of reaction
Definition
The difference between the energy absorbed in breaking bonds and that released in forming bonds; represented by ∆H
Term
Enthalpy change
Definition
Heat of reaction
Term
Endothermic Process
Definition
A chemical change (like bond breaking) that absorbs heat and has a positive ∆H
Term
Exothermic Process
Definition
A chemical change (like bond formation) that releases heat and has a negative ∆H
Term
Spontaneous process
Definition
A process that, once started, proceeds without any external influence
Term
Entropy
Definition
A measure of the disorder of a system; ∆S
Term
Free energy change
Definition
Used to describe spontaneity of a process; ∆G
Term
Exergonic
Definition
A spontaneous reaction or process that releases free energy and has a negative ∆G
Term
Endergonic
Definition
A non-spontaneous reaction or process that absorbs free energy and has a positive ∆G
Term
Activation energy
Definition
The amount of energy/heat needed to start a reaction; Ea
Term
Catalyst
Definition
A substance that accelerates a chemical reaction but is itself unchanged in the process
Term
Reversible reactions
Definition
A reaction which easily goes in either direction; indicated by a double arrow in equations.
Term
Chemical equilibrium
Definition
A state in which the rates of forward and reverse reactions are the same
Term
Le Chatelier’s Principle
Definition
When a stress is applied to a system at equilibrium, the equilibrium shifts to relieve the stress. The stress can be any change in concentration, pressure, volume, or temperature that disturbs original equilibrium
Term
Kinetic-Molecular theory of gases #1
Definition
A gas consists of many particles, either atoms or molecules, moving about at random with no attractive forces between them
Term
Kinetic-Molecular theory of gases #2
Definition
The amount of space occupied by the gas particles themselves is much smaller than the amount of space between particles.
Term
Kinetic-Molecular theory of gases #3
Definition
The average kinetic energy of gas particles is proportional to the Kelvin temperature
Term
Kinetic-Molecular theory of gases #4
Definition
Collisions of gas particles, either with other particles or with the wall of their container, are elastic; that is, the total kinetic energy of the particles is constant
Term
Ideal Gas
Definition
A gas that obeys all the assumptions of the kinetic-molecular theory
Term
Boyle’s law
Definition
The volume of a gas is inversely proportional to its pressure for a fixed amount of gas at a constant temperature – More pressure, less volume, same temp.
Term
Charles’s law
Definition
The volume of a gas is directly proportional to its Kelvin temperature for a fixed amount of gas at a constant pressure. – More heat, more volume, same pressure
Term
Gay-Lussac’s law
Definition
The pressure of a gas is directly proportional to its Kelvin temperature for a fixed amount of gas at a constant volume. – More heat, more pressure, same volume
Term
Avogadro’s law
Definition
The volume of a gas is directly proportional to its molar amount at a constant pressure and temperature
Term
Dalton’s law
Definition
The total pressure exerted by a gas mixture is the sum of the partial pressures of the components in the mixture.
Term
Vapor
Definition
A molecule near the surface of a liquid can break free of the liquid and escape into this gaseous state
Term
Vapor pressure
Definition
The contribution that the gas molecules make to the total pressure of the gas above the liquid according to Dalton’s law
Term
Boiling
Definition
Bubbles of vapor form under the surface and force their way to the top of the liquid
Term
Surface tension
Definition
The resistance of a liquid to spread out and increase its surface area; caused by the difference between the forces experienced by molecules at the surface and these experienced by molecules in the interior.
Term
Specific heat
Definition
The capacity to absorb a large quantity of heat while changing only slightly in temperature
Term
Heat of vaporization
Definition
The ability of water to carry away a large amount of heat with it evaporates
Term
Brønsted-Lowry acid
Definition
Any substance that is able to give a hydrogen ion to another molecule or ion, and need not occur in water
Term
Brønsted -Lowry base
Definition
a substance that accepts a hydrogen ion from an acid, and need not occur in water
Term
Amphoteric
Definition
Substances like water, which can react as either an acid or a base depending on the circumstances.
Term
Dissociation
Definition
The splitting apart of an acid in water to give H+ and an anion
Term
pH
Definition
A measure of the acid strength of a solution; the negative common logarithm of the H3O+ concentration
Term
Buffer
Definition
A chemical reaction that keeps hydrogen ions from getting too high
Term
Nuclear reaction
Definition
A reaction that changes an atomic nucleus, usually causing the change of one element into another
Term
Nuclear decay
Definition
The spontaneous emission of a particle from an unstable nucleus
Term
Transmutation
Definition
The resulting change of one element into another
Term
Alpha emission
Definition
The emission of 2 protons and 2 neutrons as an α particle from an unstable radioactive nucleus, resulting in a positive charge
Term
Beta emission
Definition
The result of a neutron decomposing into a proton and an electron, retaining the proton in the nucleus and emitting the electron as a β particle, resulting in a negative charge
Term
Gamma emission
Definition
The emission of photons which have no charge
Term
Positron emission
Definition
The conversion of a proton in the nucleus into a neutron plus an ejected positron, a ‘positive electron,” which has the same mass as an electron but a positive charge
Term
Electron Capture
Definition
A process in which the nucleus captures an inner-shell electron from the surrounding electron cloud, thereby converting a proton into a neutron.
Term
Half-life
Definition
The amount of time required for one-half of the radioactive sample to decay
Term
Nuclear fission
Definition
The fragmenting of heavy nuclei
Term
Nuclear fusion
Definition
The joining together of light nuclei
Term
Chain reaction
Definition
A reaction that is self-sustaining
Term
Critical Mass
Definition
The minimum amount of radioactive material needed to sustain a nuclear chain reaction
Supporting users have an ad free experience!