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Study Guide Chapter 2: Atoms
Classification of Mattero Elements: Memorize symbols
Elemental form: some (most) elements consist of single atoms
Others exist as diatomic molecules. There are SEVEN diatomic
elements. Know
which elements are diatomic and be able to write the formula for
those
molecules
o Compounds: Understand the difference between elements
combining to formcompound (like H2O) vs elements forming a
mixture.
Interpret chemical formulao Mixtures
Heterogeneous vs Homogeneous- review OWL questions that ask you
to identifysamples as Heterogeneous mixtures, homogeneous mixtures,
or pure
substances
Review Daltons atomic theory. It is more important to understand
the theory then tomemorize the postulates
o How does the Law of Conservation of Mass and Law of Constant
Composition relate topoints in Daltons theory
Subatomic particleo Know charge, relative mass (in amu), and
location of p+, n0, and e-
Particles in the Nucleus (Protons and Neutrons)o Atomic # = # of
proton. This is what gives the element its identity. EVERY single
carbon
atom has 6 protons. If it had a different #, it would be a
different element
o Mass #= # protons+ # neutrons These two particles are in the
nucleus These two particles have significant mass
o Write/interpret nucleus (or isotopic) symbols- they look like
C13
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I Have had MANY people ask me about the top (mass number). This
# is oftenDIFFERENT than the mass given on the periodic table. The
periodic table reports
the AVERAGE mass of all atoms of that element. Nuclear symbols
represent the
specific information about a SINGLE atom. In the above example,
this atom of
carbon has 6 protons (atomic #=6), and 7 neutrons [atomic
mass(13)=
(6)protons +( 7) neutrons]. Definition of isotope: Atoms of the
same element with different mass
This means that atoms that are isotopes have the same # of
protons,but different number of neutrons
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Periodic Table: From section 2.5, vocabulary that is in bold
face type is important! Learn theseterms AND be able to identify
where on the periodic table the bolded terms are located. ). Do
odd # problems in back of text from section 2.3,2.4,2.5
Period Groups Halogens Main group elements Transition elements
Inner transition
elements
Metals Non-metals Metalloids Alkali metals Noble gases
Electronso Occupy ORBITALS- Know how this is different than an
ORBITo Can you recognize the shapes of s, p, and d orbitals?o
Electrons are organized according to Energy Level, then sublevel,
then orbital
