Class 12

1. Atoms
Atoms and the Periodic Table

2. Objectives:
Describe the structure of atoms in terms of
neutrons, protons, and electrons and the role of
the atomic structure in determining chemical
properties.
https://www.youtube.com/watch?v=o-3I1JGW-Ck

3. Elements
Substances that cannot be broken
down chemically into simpler
kinds of matter.
Living things are composed of 4
basic elements:
carbon, oxygen, hydrogen and
nitrogen

4. Atom
The simplest particle of
an element that retains all
the properties of that
element

5. Parts of an Atom Nucleus: The center of
the atom that houses
the neutrons and
protons
Orbitals: Area around
the nucleus that
contains the electrons

6. Orbital
A three dimensional region around a
nucleus that indicates the probable
location of an electron
Electrons in orbitals farther away from
the nucleus are more easily pulled off
because they have more energy OR
less of a pull from the protons in the
nucleus.

7. Subatomic particles: Protons,
Neutrons, and Electrons
Neutron: neutral in charge found in nucleus,
weighs a significant amount
Proton: Positive charge, found in the nucleus,
weighs a significant amount
Electron: Negative charge, found in the orbital
(not in nucleus), does NOT weigh a significant
amount

9. Valence electrons
Outermost electrons on the outermost shell,
these electrons play a role in bonding to make
compounds

10. Periodic Table
A way to organize all the chemical elements
based on their properties.
https://www.youtube.com/watch?v=WG5LxCO-
DMs

11. Atomic symbol
The abbreviation that is
used to identify each
element on the periodic
table

12. Atomic Number
Atomic number is the number
of protons. Each element has
a different number of protons,
therefore the atomic number is
used to order and organize the
elements.

13. Atomic Weight/mass
The atomic weight is equal to the total number
of protons and neutrons.
Practice calculating numbers of protons,
electrons, and neutrons