Download Atoms and the Periodic Table

Atoms and the Periodic
Table
Chapter 4 Study Guide
Section 1 – Atomic Structure
Definitions
Nucleus:
• The central region of an atom
which contains protons and
neutrons and has a positive
charge.
Proton:
• A sub-atomic particle with positive
charge found in the nucleus of an
atom.
Neutron:
• A sub-atomic particle with neutral
charge (or no charge) found in the
nucleus of an atom.
Electron:
• A sub-atomic particle with
negative charge found in the area
outside the nucleus of an atom.
Orbital:
• A region outside the nucleus of an
atom where electrons are likely to
be found.
Valence Electron:
• One or more electrons in the
outermost energy level of an
atom.
Objective 1:Explain Dalton’s
theory, and describe why it was
more successful than Democritus’s
theory
(1) List the statements that are part
of Dalton's atomic theory:
• a. Atoms make up molecules.
• b. Atoms of an element are alike.
• c. Atoms make up elements.
Objective 1
• (2) Dalton’s atomic theory was
accepted because there was evidence
to support it.
Objective 1
• (3) According to John Dalton’s
theory, atoms of the same element
are exactly alike.
Objective 1
• (4) The word atom comes from a
Greek word that means “unable to be
divided.”
Objective 1
• (5) The first person who suggested
that matter was made up of atoms
was the Greek philosopher
Democritus.
Objective 1
• (6) Dalton’s atomic theory was more
successful than Democritus's theory
because it had a scientific basis.
Objective 1
• (7) Dalton’s atomic theory stated that
every element was made of atoms
that could not be subdivided, atoms
of the same element are alike, and
atoms can join to form molecules.
Objective 1
• (8) Two or more atoms may join
together to form molecules.
Objective 1
• (9) Substances that are made of the
same type of atoms are known as
elements.
Questions?
Objective 2:State the charge, mass,
and location of each part of an
atom according to the modern
model of the atom.
Objective 2
• (10) The nucleus is made of protons
and neutrons and has a positive
charge.
Objective 2
• (11) The charge of an electron is -1.
The charge of a proton is +1. The
charge of a neutron is 0.
Objective 2
• (12) Atoms have no electric charge
because they have an equal number
of electrons and protons.
Objective 2
• (13) The nucleus of an atom has a
positive electric charge.
Objective 2
• (14) Neutrons and protons are found
in the nucleus of an atom.
Objective 2
• (15) The overall charge of an atom is
neutral.
Questions?
Objective 3: Compare and contrast
Bohr’s model of the atom with the
modern model of the atom.
Objective 3
• (16) According to Bohr’s model of
the atom, electrons behave like
planets orbiting the sun.
Objective 3
• (17) According to Bohr’s theory, an
electron’s path around the nucleus
defines its energy level.
Objective 3
• (18) According to modern atomic
theory, it is nearly impossible to
determine an electron’s exact
position or location.
Objective 3
• (19) A sodium atom, which has 11
electrons, has one (1) electron in its
third energy level. It has two (2)
electrons in its first energy level and
eight (8) electrons in the second
energy level.
Objective 3
• (20) Unlike the modern model of the
atom, Bohr’s model states that
electrons move in set paths around
the nucleus of an atom.
Objective 3
• (21) Bohr’s model of the atom
compares electrons to planets.
Objective 3
• (22) According to modern atomic
theory, the exact location of an
electron is uncertain.
Objective 3
• (23) A region in which there is a high
probability of finding an electron is
called an orbital.
Objective 3
• (24) Valence electrons are the
negatively charged particles found in
the outermost energy level of an
atom.
Objective 3
• (25) An area of an atom where
negatively charged particles are
likely to be found are called orbitals.
Questions?