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the ability of a substance to undergo a change that transforms it into a different substance
the process by which one or more substances change to produce one or more different substances
a blend of two or more kinds of matter, each of which retains its own identity and properties
a change in a substance that does not involve a change in the identity of the substance
a characteristic that can be observed or measured without changing the identity of the substance
a substance that has a fixed composition and differs from a mixture in that every sample of a given pure substance has exactly the same characteristic properties and composition
a logical procedure for gathering information about the natural world, in which experimentation and observation are used to test hypotheses.
a specific portion of matter in a given region of space that has been selected for study during an experiment or observation
a ratio derived from the equality between two different units that can be used to convert from one unit to the other.
Le Système International d'Unités, or the International System of Units, which is the measurement system that is accepted worldwide
a value calculated by subtracting the experimental value from the accepted value, dividing the difference by the accepted value, and then multiplying by 100
numbers are written in the form M x 10^n, where the factor M is a number greater than or equal to 1 but less than 10 and n is a whole number
any digit in a measurement that is known with certainty plus one final digit,which is somewhat uncertain or is estimated.
law of conservation of mass
Mass is neither destroyed nor created during ordinary chemical reactions or physical changes
law of definite proportions
a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound
law of multiple proportions
if two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers
short-range proton-neutron, proton-proton, and neutron-neutron forces hold the nuclear particles together
average atomic mass
the weighted average of the atomic masses of the naturally occurring isotopes of an element
the amount of a substance that contains as many particles as there are atoms in exactly 12g of carbon-12
The general term for any isotope of any element; another term for an atom that is identified by the number of protons and neutrons in its nucleus
a form of energy that exhibits wavelike behavior as it travels through space
a state in which an atom has a higher potential energy than it has in its ground state
series of specific wavelengths of emitted light created when the visible portion of light from excited atoms in shined through a prism
Heisenberg uncertainty principle
it is impossible to determine simultaneously both the position and velocity of an electron or any other particle
magnetic quantum number
the quantum number that indicates the orientation of an orbital around the nucleus
orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin
noble gas configuration
An outer main energy level fully occupied, in most cases, by eight electrons
pauli exclusion principle
no two electrons or protons or neutrons in a given system can be in states characterized by the same set of quantum numbers
a three dimensional region around the nucleus that indicates the probable location of an electron
a mathematical description of the wave properties of electrons and other very small particles
spin quantum number
The quantum number that has only two possible values, +1/2 and -1/2, which indicate the two fundamental spin states of an electron in an orbital
highest occupied energy level
the electron-containing main energy level with the highest principal quantum number
one of the 14 elements with atomic numbers from 90 (thorium, Th) through 103 (lawrencium, Lr)
the physical and chemical properties of the elements are periodic functions of their atomic numbers
an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column, or group
the elements of Group 1 of the periodic table (lithium, sodium, potassium, rubidium, cesium, and francium)
one-half of the distance between the center of identical atoms that are not bonded together.
the formation of ions from solute molecules by the action of the solvent; any process that results in the formation of an ion
an electron that is available to be lost gained or shared in the formation of chemical compounds
a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together
chemical bonding that results from the electrical attraction between large numbers of cations and anions
nonpolar 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
polar covalent bond
a covalent bond in which the bonded atoms have an unequal attraction for the shared electrons
the distance between two bonded atoms at their minimum potential energy, that is, the average distance between two bonded atoms
A formula that indicates the relative numbers of atoms of each kind in a chemical compound by using atomic symbols and numerical subscripts
electron dot notation
an electron configuration notation in which only thevalence electrons of an atom of a particular element are shown, indicated by dotsplaced around the element's symbol
formulas in which atomic symbols represent nuclei and inner-shell electrons, dot-pairs or dashes between two atomic symbols represent electron paris in covalent bonds, and dots adjacent to only one atomic symbol represent unshared electrons
A pair of electrons that is not involved in bonding and that belongs exclusively to one atom.
a chemical formula of a molecular compound that shows the kinds and numbers of atoms present in a molecule of a compound
chemical compounds tend to form so that each atom, by gaining,losing, or sharing electrons, has an octet of electrons in its highest occupied energy level
the bonding in molecules or ions that cannot be correctly represented by a single Lewis structure
a formula that indicates the location of the atoms, groups, or ions relative to one another in a molecule and that indicates the number and location of chemical bonds
a pair of electrons that is not involved in bonding and that belongs exclusively to one atom
the simplest collection of atoms from which an ionic compound's formula can be established
composed of positive and negative ions that are combined so that the numbers of positive and negative charges are equal
the energy released when one mole of an ionic crystalline compound is formed from gaseous ions
the ability of a substance to be drawn, pulled, or extruded through a small opening to produce a wire
dipole dipole forces
polar molecules orient themselves so that oppositely charged ends are near eachother
orbitals of equal energy produced by the combination of two or more orbitals on the same atom
the mixing of two or more atomic orbitals of similar energies on the same atom to produce new orbitals of equal energies
the intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule
london dispersion forces
intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles
repulsion between the sets of valence-level electrons surrounding an atom causes these sets to be oriented as far apart as possible
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