Download Chapter 03 - Milton

Chapter 3: Atomic Structure
Objectives
Describe the Historical evolution of the atom
List the isotopes of Hydrogen and their properties.
 Describe and find critical problems of the Dalton atom,
 Calculate average atomic mass
the plum-pudding atom, and Rutherford’s atom
 Calculate and perform molar conversions
 Describe Thompson’s and Rutherford’s experiments
 Write and interpret two isotope notations
A. Aristotle vs. Democritus
Aristotle
Democritus
Winner:____________________
B. Dalton’s Atomic Theory
Theory
The invention of the _______________ led to better experiments.
Dalton’s Atomic Theory:
1) All Matter is composed of ___________________
2) Atoms of a given element are _______________________
in size mass and properties
3) Atoms cannot be subdivided, _____________________________________
4) Atoms combine in __________________________________to form compounds
5) In chemical reactions atoms are _____________________________________
Problems
Problems with Dalton’s Theory:
Dalton Atom
The Democritus/Dalton Atom:
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Dalton’s ideas still
around
Dalton’s Ideas that are still believed:
_________________________________ Matter cannot be created or destroyed in any
process
__________________________________ When elements combine, they do so in
simple whole number ratios.
Examples:
__________________________________ When two elements combine two or more
ways to form different compounds, they still form in simple whole number ratios
Examples:
C. JJ Thompson & The
electron
Label the parts and cathode rays
Show effect of negative charge
What was discovered: __________________________
Thompson’s Atomic Model: __________________________ Sketch:
D. Rutherford and the
nucleus
Sketch of experiment:
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Observations:
Rutherford had discovered the _________________.
Conclusions
Conclusion:
More than _______ of the mass of an atom is located in the _______________.
The atom is more than _______ empty space.
Rutherford model
and flaw
The Rutherford Model of the atom:
MAJOR FLAW:
E. Protons, Electrons,
Neutrons
Particle
Symbol
Charge
Mass
Location
Atom’s mass comes from ___________________________ or __________________.
Atom’s volume comes from ___________________________.
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F. Isotopes
Isotopes are different forms of the same __________________
But have a different _____________ or number of ___________________.
Designating
Isotopes
Hyphen Notation
Nuclear Symbol
Generic
Examples
G. Isotopes of Hydrogen
Hyphen
Notation
Nuclear
Symbol
Other name
# Protons
# Neutrons
Mass amu
Mass =
H. Average Atomic Mass

Mass of 12C atom = _______________________

1/12 the mass of

Mass of 1 proton = ____________________
12
C defined as ______________________.
Mass of 1 neutron = ___________________
Mass of 1 electron = ___________________
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_____________________________ is the weighted average of an elements isotopes
found in nature. Ignores man-made isotopes.
Avg
Atomic =
mass
Equation
Sample problem
I.
The Mole
Calculate the avg. atomic mass of oxygen if its abundance in nature is 99.76%
17
O, and 0.20% 18O.
16
O, 0.04%
What is a mole?

A pair
=
A score
=
A quartet =
A gross
=
A dozen
J. Molar Mass
Elements
=

A MOLE = _____________________________________

Called ______________________________________________
_____________________ Mass of one mole of an element or compound
AKA:
For Elements:
Carbon = _________________
Pd = ______________________
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Compounds
For Compounds: _________________________________________________
Examples
NaCl
C12H22O11
NaHCO3
(NH4)2SO3
K. Molar Conversions
The Big 3 Conversions
How many moles of carbon are in 26.36 g of carbon?
How many molecules are in 2.50 moles of C12H22O11?
Find the mass of 2.1E24 molecules of Mn(NO3)2.
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