Science Chapter 14 Flashcards
a group of two or more atoms linked by chemical bonds to form distinct units
molecule
a combination of chemical symbols and numbers showing the type and number of atoms in each compound
chemical formula
the sum of the atomic masses of all the atoms in a molecule
molecular mass
substances composed of atoms of two or more elements bonded together
compounds
molecules that have the same molecular formula but different structural formulas
isomer
a substance that has the same physical properties throughout and consists of only one type of atom, one type of molecule, or one nonmolecular compound; all pure substances are either elements or compounds
pure substances
a substance that has the same physical properties throughout the substance
homogenous
three-dimensional representation of a molecule that shows its shape and the position of its atom
molecular model
a substance composed of several pure substances that are physically mixed but not chemically united
mixture
a homogeneous mixture that exists because of attraction between atoms, molecules, or ions
solution
a substance in a solution that is dissolved
solute
a substance in a solution that does the dissolving
solvent
describes a mixture in which the molecules of the mixed substances are not completely mixed
heterogenous
a mixture containing tiny suspended clumps or particles
colloid
the appearance of a blue-tinged milky or cloudy effect within a colloid when a light shines through it
tyndall effect
a heterogeneous mixture whose particles are large enough that they will settle
suspension
an attractive force that links atoms to form molecules and compounds
chemical bond
The most important factor affecting how chemical bonds form is the number of ______ in the valence shell of each atom involved.
electrons
a chemical bond resulting from the sharing of valence electrons between atoms
covalent bond
Covalent bonds typically form between two _______
nonmetals
a covalent bond involving an electron
single bond
a covalent bond formed by the sharing of two pairs of electrons
double bond
a covalent bond in which three pairs of electrons are shared
triple bond
a diagram showing the locations of all the atoms and valence electrons in a molecule or ion
lewis structure
describes electrons that are part of more than one chemical bond, being shared by more than two atoms
delocalized
the property of an element that describes how strongly atoms of that element pull on electrons in chemical bonds
electronegativity
a covalent bond in which both atoms share their electrons equally and the electrons are not pulled closer to one atom than to the other
nonpolar bond
a covalent bond in which the more electronegative atom pulls the shared electrons toward itself
polar bond
a charge less than that of a proton or electron
partial charge
a molecule that has opposite partial charges on opposite ends of the molecule; one end of a polar molecule has a negative partial charge, and the other end has a positive partial charge
polar molecule
a substance consisting of atoms covalently bonded into a large structure that does not contain a specific number of atoms
covalent network
Although covalent networks do not contain a specific number of atoms, they always combine in ____ ratio of elements.
fixed
the simplest ratio of atoms in a covalent network
formula unit
the mass of a formula unit
formula mass
a negative ion
anion
a positive ion
cation
a bond formed by the attraction between the oppositely charged ions
ionic bond
Ionic bonds typically form between a ____ and a ______
metal, nonmetal
an ion formed from a group of atoms
polyatomic ion
an orderly geometric arrangement consisting of millions or billions of ions all bonded by electrical attraction
ionic crystal
the bonding in metals in which valence electrons are shared by all the atoms in the metal
metallic bonding
a repeating unit in a crystalline solid arranged in a three-dimensional pattern
unit cell
Molecules not arranged in a repeating, orderly pattern are
amorphous solids
a chemical reaction that causes thermal energy to be absorbed and stored in the chemical bonds of the products
endothermic reaction
