Module 2 Flashcards
Atoms consist of
a single nucleus
with positive charge
surrounded by
a cloud of negatively charged
electrons.
When atoms approach one another closely,
electron clouds interact with each other and with
the nuclei.
If this interaction is such that the total energy of
the system is
Lowered
atoms bond
together to form a
molecule.
consist of an aggregation of atoms held together by valence forces .
Molecules
A molecule consist of ____________ held together by valence forces
Aggregation of atoms
group of two or more atoms that form the smallest identifiable unit
Molecules
Molecules are a group of two or more atoms that form the smallest identifiable unit into which
a pure substance can be divided and
still retain the composition and chemical
properties of that substance.
Contain two atoms that are chemically bonded.
Diatomic molecules
Contain two identical atoms that are chemically bonded.
Homonuclear
Contain two different atoms that are chemically bonded.
Heteronuclear
Molecules containing more than two atoms.
Polyatomic molecules:
The fundamental principle of chemistry is that
the atoms of
different elements can combine with one another to form
chemical compounds.
a distinct substance formed by chemical
union of two or more elements in definite proportion by weight.
Chemical compound
Subscripts represent the
number of atoms
True or False: It is impossible for the same kind of atoms to combine in the same
proportion to form a different type of molecule.
False
identical atoms bonding together with identical
proportions and differ only in arrangements.
Isomers
isomers are identical atoms bonding together with identical
proportions and differ only in __________.
Arrangement
Example of isomers
Ethyl alcohol ( CH3CH2OH)
Methyl ether (CH3OCH3
are atoms (assemblies of atoms) that have a net electrical charge.
Ions
ions that contain fewer electrons than protons have a net positive charge.
Cation
ions that contain more electrons than protons have a net negative charge.
Anions
contain both cations and anions in a ratio that
results in no net electrical charge.
Ionic Compounds
electrons are shared between bonded
atoms and are simultaneously attracted to more than one nucleus.
Covalent compounds
Contrast to covalent compounds, ionic compounds contain _________________ rather than
discrete neutral molecules.
Anions and cations
Ionic Compounds are held together by
the attractive electrostatic
interactions between cations and anions.
The cations and anions are
arranged in space to form
extended three-dimensional array that
maximizes the number of electrostatic interactions
minimizes the
number of repulsive electrostatic interactions.
contain both cations in a ratio that results in zero
electrical charge.
Ionic compounds
If the electrostatic energy is positive, the particles ________ each other;
Repel
If the electrostatic energy is negative, the particles _________
each other.
are attracted to
The name of a _______________ is simply the name of the element followed by
the word ion.
Monoatomic cation
an ion’s positive charge is indicated by a roman numeral in
parentheses after the element name, followed by the word ion.
Stock System
The ______________ uses two suffixes (-ic and -ous) that
are appended to the stem of the element name.
Common System
The ____________ suffix represents the greater of the two cation charges,
-ic
the _________ suffix represents the lower one.
-ous
In many cases, the stem
of the element name
comes from the ________
name of the element.
Latin
