Atomic Structure/Theory and Periodic Table Study Guide
Unit 3: Atomic Structure/Theory and Periodic Table
Friday, October 11, 2013
Atomic Structure/Theory and Periodic Table Study Guide Atom -What is an Atom? smallest part of element: the smallest portion into which an element can be divided and still retain its properties, made up of a dense, positively charged nucleus surrounded by a system of electrons
P
Proton: is a particle with a positive electric charge present in the nucleus of each atom. The number of protons in each atom is its atomic number
Neutron: is a
particle which has no net electric charge present in the nucleus of each atom.
Electron: is a particle
Atomic Theory
with a negative electric charge orbiting the nucleus of each atom.
Y
S
I
C
A
L
S
C
I
E
N
C
E
Definitions Mass Number The total number of protons and neutrons in a nucleus Atomic Number The number of protons in an atom's nucleus
Interesting Facts: -Atoms cannot be divided using chemicals. They do consist of parts, which include protons, neutrons, and electrons, but an atom is a basic chemical building block of matter
Sub-atomic Particals
H
Atomic Weight The average mass of naturally occurring isotopes of an atom.
Atomic Models Democritus: Ancient Greek philosopher who came up with the idea of the atom. Atom comes from the Greek atomos meaning indivisible. Aristotle: Ancient Greek philosopher who disagreed with Democritus and said that matter was infinitely divisible.
Thomson: English physicist who discovered the electron in 1897. Atoms are solid spheres made-up of a solid positive mass (or core) with tiny negative particles embedded in the positive core (Plum Pudding Model)
Niels Bohr: He developed the theory of electron orbitals, which stated that electrons could only occupy specific regions around an atomic nucleus.
Schroedinger & John Dalton: Proposed in Rutherford: Gold Foil test Heisenberg: the electrons 1803 that atoms are seen as solid, indestructible spheres (like billiard balls)
1) All elements are composed of atoms (Cannot be divided or destroyed).
proved that the nucleus is posi- moving around the nucleus in a tive and the electrons are out- "cloud" of energy levels side the nucleus. The Planetary Model-Proposes that the atom is really mostly empty space and the electron spins around the nucleus
2) Atoms of the same element are exactly alike. Atoms of different elements are different from each other.
3) Atoms of two or more elements can combine to form compounds. (HINT- Atoms can be divided, but no longer are that element.)
U n i t
3 :
A t o m ic
S tr u c t u r e / T h e o r y
a n d
P e r i o d i c Ta b l e
PERIODIC TABLE - an organizational system for elements. Elements are arranged in rows going from right to left called Periods and columns going up and down called Families or Groups. Elements in the same period have the same number of energy levels. The period number is the same as the number of energy levels Atoms get more massive as you move from left to right across the periodic table The atomic radii decreases as you move left to right across the periodic table
Group 1 or Alkali metals - Elements whose atoms have 1 outer-shell electron; they are very reactive Group 2 or Alkaline Earth Metals - Elements whose atoms have 2 outer-shell electrons Group 3 - Elements whose atoms have 3 outer-shell electrons (Boron family) Group 4 - Elements whose atoms have 4 outer-shell electrons (Carbon Family)
Group 5 - Elements whose atoms have 5 outer-shell elecElements in the same family / group have similar proper- trons (Nitrogen Family) ties because they have a similar electron arrangement. Group 6 - Elements whose atoms have 6 outer-shell electrons (Oxygen Family) Metals are on the left hand side of the table Non-metals are on the right-hand side of the table. Metalloids are between the metals and non-metals.
Group 7 or Halogens - Elements whose atoms have 7 outer-shell electrons Group 8 or Noble Gases - Elements whose atoms have full outer shells so they are very unreactive.
Friday, October 11, 2013
Atomic Structure/Theory and Periodic Table Study Guide Atom -What is an Atom? smallest part of element: the smallest portion into which an element can be divided and still retain its properties, made up of a dense, positively charged nucleus surrounded by a system of electrons
P
Proton: is a particle with a positive electric charge present in the nucleus of each atom. The number of protons in each atom is its atomic number
Neutron: is a
particle which has no net electric charge present in the nucleus of each atom.
Electron: is a particle
Atomic Theory
with a negative electric charge orbiting the nucleus of each atom.
Y
S
I
C
A
L
S
C
I
E
N
C
E
Definitions Mass Number The total number of protons and neutrons in a nucleus Atomic Number The number of protons in an atom's nucleus
Interesting Facts: -Atoms cannot be divided using chemicals. They do consist of parts, which include protons, neutrons, and electrons, but an atom is a basic chemical building block of matter
Sub-atomic Particals
H
Atomic Weight The average mass of naturally occurring isotopes of an atom.
Atomic Models Democritus: Ancient Greek philosopher who came up with the idea of the atom. Atom comes from the Greek atomos meaning indivisible. Aristotle: Ancient Greek philosopher who disagreed with Democritus and said that matter was infinitely divisible.
Thomson: English physicist who discovered the electron in 1897. Atoms are solid spheres made-up of a solid positive mass (or core) with tiny negative particles embedded in the positive core (Plum Pudding Model)
Niels Bohr: He developed the theory of electron orbitals, which stated that electrons could only occupy specific regions around an atomic nucleus.
Schroedinger & John Dalton: Proposed in Rutherford: Gold Foil test Heisenberg: the electrons 1803 that atoms are seen as solid, indestructible spheres (like billiard balls)
1) All elements are composed of atoms (Cannot be divided or destroyed).
proved that the nucleus is posi- moving around the nucleus in a tive and the electrons are out- "cloud" of energy levels side the nucleus. The Planetary Model-Proposes that the atom is really mostly empty space and the electron spins around the nucleus
2) Atoms of the same element are exactly alike. Atoms of different elements are different from each other.
3) Atoms of two or more elements can combine to form compounds. (HINT- Atoms can be divided, but no longer are that element.)
U n i t
3 :
A t o m ic
S tr u c t u r e / T h e o r y
a n d
P e r i o d i c Ta b l e
PERIODIC TABLE - an organizational system for elements. Elements are arranged in rows going from right to left called Periods and columns going up and down called Families or Groups. Elements in the same period have the same number of energy levels. The period number is the same as the number of energy levels Atoms get more massive as you move from left to right across the periodic table The atomic radii decreases as you move left to right across the periodic table
Group 1 or Alkali metals - Elements whose atoms have 1 outer-shell electron; they are very reactive Group 2 or Alkaline Earth Metals - Elements whose atoms have 2 outer-shell electrons Group 3 - Elements whose atoms have 3 outer-shell electrons (Boron family) Group 4 - Elements whose atoms have 4 outer-shell electrons (Carbon Family)
Group 5 - Elements whose atoms have 5 outer-shell elecElements in the same family / group have similar proper- trons (Nitrogen Family) ties because they have a similar electron arrangement. Group 6 - Elements whose atoms have 6 outer-shell electrons (Oxygen Family) Metals are on the left hand side of the table Non-metals are on the right-hand side of the table. Metalloids are between the metals and non-metals.
Group 7 or Halogens - Elements whose atoms have 7 outer-shell electrons Group 8 or Noble Gases - Elements whose atoms have full outer shells so they are very unreactive.
