Chapter 14 Flashcards
What is a group of two or more atoms linked by chemical bonds to form distinct units?
molecule
What is a combination of chemical symbols and numbers showing the type and number of atoms in each compound?
chemical formula
What are substances composed of atoms of two or more elements bonded together?
compound
What is the sum of the atomic masses of all the atoms in a molecule?
molecular mass
What are molecules with the same molecular formula but different structural formulas?
isomer
What is 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 substance
What is a three-dimensional representation of a molecule that shows its shape and position of its atoms?
molecular model
What is a substance that is composed of several pure substances that are physically mixed but not chemically united?
mixture
What is a homogeneous mixture that exists because of attraction between atoms, molecules or ions?
solution
What is a substance in a solution that is dissolved?
solute
What is a substance in a solution that does the dissolving?
solvent
What is a substance that has the same physical properties throughout?
homogeneous
What describes a mixture in which the molecules of the mixed substances are not completely mixed?
heterogeneous
What is a mixture containing tiny suspended clumps or particles?
colloid
What is a heterogenous mixture whose particles are large enough that they will settle?
suspension
What is an attractive force that links atoms to form molecules and compounds?
chemical bond
What is the most important factor affecting how chemical bonds form?
the number of electrons in the valence shell
What is a chemical bond resulting from the sharing of electrons between atoms?
covalent bond
What does a covalent bond typically form between?
two nonmetals
What is a covalent bond involving the sharing of a single pair of electrons?
single bond
What is a covalent bond formed by the sharing of two pairs of electrons?
double bond
What is covalent bond in which three paris of electrons are shared?
triple bond
What is a diagram showing the locations of all the atoms and valence elctrons in a molecule or ion?
Lewis structure
What describes electrons that are part of more than one chemical bond, being shared by more than two atoms?
delocalized
What is the property of an element that describes how strongly atoms of that element pull on electrons in chemical bonds?
electronegativity
What is a covalent bond in which both atoms share their electrons and the electrons are not pulled closer to one atom than to the other?
nonpolar bond
What is a covalent bond in which the more electronegative atom pulles the shared electrons toward itself?
polar bond
What is a charge less than that of a proton or electron?
partial charge
What is 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
What is any two-atom molecule with a polar bond?
a polar molecule
What is a substance consisting of atoms covalently bonded into a large structure that does not contain a specific number of atoms?
covalent network
What is the simplest ratio of atoms in a covalent network (or any other nonmolecular compound)?
formula unit
What is the mass of a formula unit?
formula mass
What is a negative ion?
anion
What is a positive ion?
cation
What is a bond formed by the attraction between the oppositely charged ions?
ionic bond
What is an ion formed from a group of atoms?
polyatomic ion
What is an orderly geometric arrangement consisting of millions or billions of ions all bonded by electrical attraction”?
ionic crystal
What is the bonding in metals in which valence electrons are shared by all the atoms in the metal?
metallic bonding
What is the rule in which the name of the last element in changed to end in -ide?
Covalent Bond Rule 1
What is the rule in which prefixes are added to each element indicating how many atoms are present?
Covalent Bond Rule 2
What is the rule in which the names of the ions are listed with the cations first?
Ionic Bond Rule 1
What is the rule in which the charged of the ions in an ionic compound must add to zero?
Ionic Bond Rule 2
What is the rule in which an element can form more than one monotonic cation and the charge of the ion is included as a Roman numeral?
Ionic Bond Rule 3
What are combinations of chemical symbols and numbers showing the type and number of atoms in each compound?
chemical formulas
What tells how many of each type of atom are in a molecule; covalent networks and ionic compounds do not have molecular formulas because they are not made of molecules?
molecular formula
What shows the general arrangement of the atoms in a molecule?
structural formula
What shows only the simplest ratio of atoms in a compound?
empirical formula
What are the forces that bind molecules to form larger structures?
intermolecular forces
By causing both cohesion and adhesion in molecular compounds, what do intermolecular forces act as?
the “glue” that hold many structures together
What are the three categories of intermolecular forces?
dipole-dipole forces, London forces, and hydrogen bonds
What is the intermolecular force of attraction between oppositely charged ends of polar molecules?
dipole-dipole forces
What is the weak intermolecular force caused by random shifting of electron clouds and mutual polarization; occurs between all molecules, whether polar or nonpolar?
London force
What is the strength of the London force proportional to?
the size of the molecule
What are the only intermolecular forces that affect nonpolar molecules?
London forces
What is the unusually strong intermolecular force present when hydrogen covalently bonds to a highly electrongenative atom?
hydrogen bond
What is a repeating unit in a crystalline solid arranged in a three-dimensional pattern?
unit cell
What are molecules not arranged in a repeating, orderly pattern called?
amorphous solids
In general, how do the intermolecular forces between the molecules of a solid affect the melting point?
the stronger the intermolecular forces, the higher the melting point
Do nonmolecular substances or molecular substances usually have a higher melting point?
nonmolecular substances
What does vapor pressure and the boiling point of a molecular substance depend primarily on?
on the molecular mass of the molecules and the types of intermolecular forces between them
What is a homogeneous mixture?
solution
What is the substance that does the dissolving in a solution?
solute
What is the substance that does the dissolving in a solution?
solvent
Does each type of solution form the same?
no
When the solute is a solid, can it flow?
no
What is to break apart into ions when dissolved in water?
dissociate
What are three ways to increase the rate of dissolving in a solution?
increasing the temperature, agitating the solution, or increasing the surface area
What is the ability of one substance to dissolve in another substance to form a solution?
solubility
What means able to dissolve easily in a particular substance?
soluble
What means not able to dissolve easily in a given substance?
insoluble
What is a substance that comes out of a solution that has more solute that it can hold through the process of precipitation?
precipitate
What is the most important factor that affect solubility?
the nature of the substances
What is a measure of how much solute is dissolved in a given amount of solution?
concentration
How also can concentration be measured?
mass percent
What is the unit representing approximately 6.022 × 10²⁸ particles?
mole
What is a meaure of solution concentration as moles of sultes per some volume of solution?
amount concentration
What is concentration measured as the mles of a solute in a given mass?
molality
What is the process of mixing molecules of one substance with another substnace by random molecular motion?
diffusion
What is one-way diffusion through a semipermeable membrane?
osmosis