Download Atomic Structure Test – Study Guide

Atom/Elements Study Guide
Basic Concepts
The atom is the smallest particle that cannot be broken down by ordinary means; it is the
building block of all matter.
A neutral atom is one that carries no charge because the protons (+) and electrons (-) are
equal, therefore balancing each other out.
Atomic Structure
What is the electrical charge and position in the atom for each of the subatomic particles?
1. Electron - negative charge; located in a “cloud” rotating around the nucleus
2. Proton – positive charge; located in the center or nucleus of the atom
3. Neutron - no charge; located in the center or nucleus of the atom
What subatomic particles are in the nucleus of the atom and what is the charge of the
nucleus?
Protons and neutrons so the charge of the nucleus is positive
The atom is composed mostly of empty space.
Where is most of the mass of the atom located? In the nucleus
How many electrons can exist in the first shell? The second? 2, 8, 8,18
Which two subatomic particles have approximately the same mass?
Neutrons and protons
Atoms with the same number of protons but different numbers of neutrons are called
isotopes.
Periodic Table
Elements in the periodic table are arranged by atomic number OR the number of protons.
An elements properties can be predicted from its location in the periodic table.
The atomic number of an element is equal to the number of protons.
How can you find the number of neutrons in an atom? Atomic mass – atomic #
What makes one element different from another?
Using the Periodic Table
Draw a Bohr model of the element Chlorine, Cl.
2. Draw Bohr models of Carbon isotopes with atomic masses of 11, 12, and 13amu.
Extra Questions
Compare atomic number and atomic mass number. Atomic number is the number of
protons. The atomic mass number represents all of the matter in the atom – the whole
numbers represent the sum of protons + neutrons.
Atomic number = # of protons
Atomic Mass = protons + neutrons
If an atom has 43 electrons, 56 neutrons, & 43 protons, what is the approximate atomic
mass? What is the element?
Why are the atomic masses in the periodic table not whole numbers?
They are averages of the masses of atoms of each element. There can be a variety of
isotopes, atoms with the same number of protons and electrons but different numbers of
neutrons.
ATOMS TEST – STUDY GUIDE
Structure of the Atom
 Atomic Structure Worksheet (skim over)
1. The overall charge of an atom is ____________ if the number of
_________ and _____________ are the same.
 Bill Nye Video
1. In the nucleus there are two particles the _____________ and
the_________.
2. Moving around the nucleus are _______________.
3. Everything that is made of atoms is mostly
______________________.
4. What makes one atom different from another is the number of
__________ in the nucleus of the atom.
5. The atomic number is the number of ___________.

Structure of the Atom Notes
1. Protons are found in the _________ and have a ________ charge.
2. Neutrons are found in the _________ and have __________ charge
3. Electrons are found in _________________ and have a _______ charge.
4. The nucleus is _______% of the mass of the atom. Protons and neutrons have
about the _______ mass which is 1 ______. The electrons are ________ the
mass of a proton or neutron.
5. What is the atomic number of Cl? How many protons?_____ Neutrons?____
6. The Atomic Number is __________________________________.
7. The Mass Number is ____________________________________.
8. Atomic Mass is _________________________________________
_________________.
9. An isotope is _______________________________________________
___________________.
10. An ion is ___________________________________. An atom is a _________ ion
if the number of protons is greater than the number of electrons. It is a
_____________ion if the number of protons is less than the number of electrons.
1. Isotopes – know definition of isotope
2. The atomic mass is not a whole number because it is based on an _________ of
all the isotopes of an element.
Atomic Models
 Bohr Atomic Models (be able to draw a model of an atom by using the periodic
chart)
1. The _________________ tells you the # of protons in the nucleus.
2. To find the number of neutrons you subtract the atomic number from the
__________________.
3. _____ electrons fill the first energy level, _______ fill the 2nd energy level and
________ fill the 3rd energy level if it is not the last level. The last level is filled
with ________electrons.
4. Valence electrons are ______________________________________.
5. Valence electrons determine _________________________________.
6. Noble Gases do not react with other elements because _____________
____________________________.
7. Sodium wants to bond with chlorine because it has only ____ valence electron. It
wants to _____ that electron to Chlorine. Chlorine wants to take that electron
because it has ____ valence electrons and so only needs ____ more electron to
have a filled outer level.
Play “Build an Atom” PHET on level 4 to 100%