Transcript 4 nuclear symbols 1112

1. What are the three types of
radiation?
2. Draw the nuclear symbol for
bromine-80.
Day 2
12-4
Atoms defy what we thought
we knew! 1932
• James Chadwick
neutrons
discovered _________
charge
–Have no _______
–Located in the atom’s
nucleus
_______
Atoms defy what we thought we
knew! 1938
• Lise Meitner was the first to
correctly describe a nuclear
fission
________ reaction in which a large
nucleus is split into two smaller
nuclei of approximately equal size.
235U + 1n → 236
92
0
92
236
1
141
92
n
3(
)
→
Ba
+
Kr
+
92
0
56
36
U
U
Today: Is matter continuous or
discontinuous?
• What are protons, neutrons, and
electrons made of?
quarks, bosons, muons, gluons, etc!
• What about string theory?
Is there a tiniest piece of energy
that everything is made of?
Today: Is matter continuous or
discontinuous?
Is there a tiniest piece of energy that
everything is made of?
• When you ask “What is the
smallest piece?”, be certain to
specify what you want!
–Cmpd. = group of bonded atoms
–Element = single atom
–Atom = ??
Parts of Atoms, Isotopes, and
Ions
• Isotopes
–Atoms of one element
protons
• Same number of _______
neutrons
• Different numbers of ________
masses
• Different ______
Parts of Atoms, Isotopes, and
Ions
• Ions
–________
Charged atoms that have gained
electrons
or lost ________
–Examples
• Iron loses 2 electrons
+2
Fe
• Chlorine gains 1 electron
-1
Cl
Atomic number = protons = electrons
(neutral atom)
Mass # = Atomic # + neutrons
Parts of Atoms, Isotopes, and
Ions
Fundamental parts of atoms
APPROXIMATE LOCATION
CHARGE
COMPONENT
MASS (in amu) IN ATOM
electron
-1
0.00055
shells
proton
+1
1.0
nucleus
neutron
0
1.00055
nucleus
Parts of Atoms, Isotopes, + Ions
atom of any element
–Individual _____
nuclear
–Represented with a _______
symbol
A
C
• X = _______
element _______
symbol
mass _______
number
• A = ____
Z
• Z = ______
atomic _______
number
X
Parts of Atoms, Isotopes, and
Ions
• X = _______
_______
element symbol
mass number
• A = ____
_______
• Z = ______
_______
atomic number
protons number
= ______
_______
• C = ______
___
charge as__an__ion
Z
A - ___
• # neutrons = ___
Z - ___
C
• # electrons = ___
A
C
X
Z
Parts of Atoms, Isotopes, and
Ions
Mass number?
Atomic number?
# of neutrons?
Element?
Charge?
# of electrons?
19
1-
X
9
Parts of Atoms, Isotopes, and
Ions
Mass number?
Atomic number?
# of neutrons?
Element?
Charge?
# of electrons?
42
2+
X
20
Parts of Atoms, Isotopes, and Ions
1. Draw a nuclear symbol for an
element with 17 protons, 18 neutrons,
and 18 electrons
a. What element is it?
b. What is the atomic #?
c. What is the mass #?
d. What is the charge?
Practice # 2 – due NOW
Day 3 12-7
1. Thomson’s model of the atom was the
electrons
first to show _________.
2. One thing that Thomson’s model
showed incorrectly or not at all?
3. Explain how beta radiation (which is
high speed electrons) can be emitted
from the nucleus (electrons are not in the
nucleus?)?
Particles of Radioacty. + Nuc. Rxns.
• Nuclear Reactions
–What forces act in the atom?
nuclear force holds
• Strong
______ _______
protons
_______ together
nuclear force causes
•Weak
_____ _______
radioactivity
___________
–Natural radioactivity, radioactive
decay, or nuclear disintegration
is the spontaneous
___________ …
Particles of Radioacty. + Nuc. Rxns.
• Nuclear Reactions
–Natural radioactivity, radioactive
decay, or nuclear disintegration
is the spontaneous
___________ … ________
emission
of ________
radiation from an element
due to instability of the _______.
nucleus
Particles of Radioacty. + Nuc. Rxns.
• Nuclear Reactions
–Problems in nuclear stability
occur when there are too few
or too many ________.
neutrons
–All elements with an atomic
number greater than ___
83 are
radioactive.
Particles of Radioacty. + Nuc. Rxns.
Particles of Radioactivity
SYM
TYPE
CHARGE
BOL
alpha
beta
gam
ma

4He +2
2

-1
0e
-1

0
ALIAS
PENING.
ABILITY
helium low: stopped
nucleus by paper
medium:
electron stopped by
clothes
light
energy
high: stopped
by thick lead
and concrete
Particles of Radioacty. + Nuc. Rxns.
Particles of Radioactivity
TYPE
SYM CHARG
BOL
E
positron
0e
+1
ALIAS
+1
positive
beta
proton
1H
+1
hydrogen
nucleus
neutron
1n
0
0
1
PENING.
ABILITY
shortlived
Particles of Radioacty. + Nuc. Rxns.
• Nuclear Reactions
–The beta () particle has a
________
negative charge. How can it be
released from the nucleus?
A neutron splits into a proton and an elec.!
1n
0
→
1p+
1
0
–
+ - 1e
Practice # 2 – due NOW
1. Fill in the missing nuclear symbol and answer the
following questions.
239
92 U

239
93 Np
+
0
_____
-1 e
Day 4
12-8
- what type of radiation is being produced in
this reaction?
- what type of charge does this radiation
particle carry?
- How does this type of radiation compare to
the other two major types?
2. What alpha-emitting element is used to produce
actinium-227?
Get out your lab and
determine what you need to
finish.
Postlabs are due Wednesday 12-4
(tomorrow).
Test is Monday 12-9!!!
Day 3
12-2
Station A = Exps. 2 and 3
Station B = Exps. 4 and 5
Station C = Exps. 6 and 7
Atom
Isotope
Mass number
Beta
Alpha
Atomic number
Ion
Energy level
Electron cloud
Empty space
Quark
Gold Foil Experiment
Positron
Nuclear Force
Proton
Planetary model
Cathode Ray Chadwick
Neutron
Nucleon
J.J. Thomson Plum pudding model
Marie Curie
Law of Definite Proportions
1. Explain the parts of the model and
specifically what each part represents.
2. Explain how or why the model was
developed.
3. Explain what it represents well (its
strengths as a model).
4. Explain some of its limitations (its
weaknesses).
1. Explain the parts of the model and
specifically what each part represents.
2. Explain how or why the model was
developed.
3. Explain what it represents well (its
strengths as a model).
4. Explain some of its limitations (its
weaknesses).
QUICK
TALK
Thomson
Bohr
Atom
Dalton
Proton
Plum Pudding model
Electron cloud
Neutron
Law of Definite
Proportions
Alchemists
Mendeleev
We have Atoms! - 1850’s
Cathode Ray Tubes
11-19
1. Rutherford and Soddy showed that
radioactivity produces new
________________.
2. What information can you obtain
from a nuclear symbol?
What is the last thing you have in your notes?
1. Explain the parts of the model and
specifically what each part represents.
2. Explain how or why the model was
developed.
3. Explain what it represents well (its
strengths as a model).
4. Explain some of
its limitations
(its weaknesses).
Protons
Neutrons
Bohr’s model
Beta particles
Gamma rays
Electron cloud
Nucleons
Atom
Plum Pudding model
Dalton
Quarks
Gold Foil Experiment
Mendeleev Song
http://www.youtube.com/watch?v=k
uQ0Um4Wcz0