Transcript Unit 2 Review - RHSChemistry

Unit 2 Review
For a specific element the number of
______________
is the same but the number of
Protons
Neutrons
Electrons
________
and ___________
may vary.
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Multiple forms of the same element with varying
Isotopes
numbers of neutrons are called ________________.
The same element with extra or not enough electrons
are called ________.
Ions
# of Neutrons
# of Protons
Mass number = _______________
+ _______________
What are the two ways to write an isotope of carbon with
7 neutrons?
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Carbon-13
1. _______________
13
6C
2. _______________
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Name the element which has:
a.
b.
c.
d.
1 proton _____________
Hydrogen
4 n0, 3 p+, 3 e-________
Lithium
Iron
30 n0, 26 e-, 26 p+_____________
Argon
18 e-, 22 n0, 18 p+_____________
Mickey
Minnie
Barry (the Puma)
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What are valence electrons?
_________________________________
The electrons in an atom’s outer most orbitals
___
How many valence electrons in the
following atoms:
3
a. Al ________
c. Mg _________
2
5
b. P __________
R.I.P. Tina (the llama)
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How do the electron configurations for the
following elements end?
a. K _________
4s1
4p6
c. Kr _________
2p3
b. N __________
How are mass number and atomic mass different?
Mass number is the mass of the protons and neutrons
combined. Atomic mass is the average mass of the element’s
isotopes.
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Put the following people in order and then
tell what they contributed to the
understanding of the atom:
- Rutherford, Dalton, Aristotle, Thomson,
Bohr, Democritus, Chadwick
Democritus: came up with the first idea of an atom
Aristotle: disagreed with Democritus
Dalton: published his atomic theory (5 principles) in early 1800’s
* almost all still true today.
Thomson: used Cathode Ray Tube Experiment to discover the first
subatomic particle, the electron.
Rutherford: used the Gold Foil Experiment to prove the existence
of a small, dense, positive nucleus.
Bohr: said electrons are in energy levels
Chadwick: discovered the neutron (hard to find b/c neutral & in center.)
Quantum Mechanics – current model of the atom.
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Explain the gold-foil experiment and the
cathode-ray tube experiment. Remember
Gold Foil Essay..
Review notes
Bob (the Manatee)
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Why are atoms neutral?
_____________________________
Equal numbers of negative electrons and positive protons
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What is the charge of the nucleus of a Carbon
atom?
positive
_____________________________
Particle
Charge
Mass
Location
Electron
Negative
Approximately 0
Space surrounding
nucleus
Proton
Positive
1
Inside nucleus
Neutron
Neutral
1
Inside nucleus
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Complete the table:
Include the mass number and atomic number in
names or symbols as discussed in class.
Element
Symbol
#p
4
#n
#e
Beryllium-9
Be
Vanadium-44
V
23
Al
13
15
13
H
1
1
1
Aluminum-28
Hydrogen-2
5
4
21
23
Mass # Atomic
Number
9
4
44
23
28
2
13
1
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Complete the table:
Element
Electron
Configuration
Beryllium
1s2 2s2
Sn (No
Orbital
Notation)
S
Orbital
Notation
Electron
Dot
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Write the noble gas configuration for
krypton. Also, draw the electron dot
diagram.
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What shapes are s and p orbitals?
S- Sphere
P- Dumbells
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Explain, in your own words ground state
for electrons.
Ground state electrons in the lowest possible energy
level are normal.
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Explain, in your own words excited state
for electrons.
Excited state electrons take on energy and jump energy
levels.
George (the Geko)
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Why did the chemicals used in the
“somewhere in the rainbow” lab give off
colors when heated?
The electrons absorbed the heat from
the burner, causing them to jump up to
the excited state. In order to return
back to “ground state” the electrons
must give off the extra energy – in the
form of light.
Paris Hilton
vs.
The Hulk
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Consider the electrons found in Sulfur.
How many total orbitals are found in
sulfur? _______
Of all these orbitals,
9
how many are found on the 2nd energy
4
level? _________
Of the orbitals found
on the second energy level, how many
different orbital shapes are there?
_________
How many electrons could fit
2
6
into the entire 2p sublevel? ______
How
many electrons could fit into one 2p
2
orbital? ___________
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Titanium has 5 naturally occurring isotopes.
Calculate the average atomic mass.
Sodium has two
isotopes. Sodium-22
and Sodium-23.
Which is more
abundant?
Sodium-23
________________
Mass (amu)
% Abundance
45.955
8.00
46.952
7.30
47.948
73.80
48.948
5.50
49.945
5.40