Download 5 Electrons in Atoms

5 Electrons in Atoms
BIGIDEA
Write the Big ldea for this chapter.
Use the "What I Know" column to list the things you know about the Big ldea. Then list the
questions you have about the Big ldea in the"What I Want to Find Out"column. As you read the
chapter, fill in the"What I Learned"column.
Kwt
What
lKnow
What lWantto Find
Science Notebook
'
71
Out
Electrons in Atoms
What lLearned
5 Electrons in Atoms
1 Light and Quantized
ffi2(G),6(8),6(c) I
EnergY
$?#eeru
l)[A
Write the Main ldea for this lesson.
#svesw B**e***.esv
Recall the definition of the ReviewVocabulary term.
radiation
radiation
F€eas
S*aesst&sY
electromagnetic radiation
Define each New Vocabulary term.
ele cIr o rn ag n eIi
c
ra
di ati o n
wavelength
frequency
amplitude
wavelength
electromag netic spectru m
quantum
trequency
Planck's constant
am?lftude
photoelectric effect
el e
clr o m agn eti c
sp e ctT um
photon
quantum
atomic emission spectrum
Planck's constant
Vholoelectric effect
Vhoton
atomi c emissi on speclrurn
Science Notebook. Electrons in Atoms
72
1 Light and Quantized Energy (continued)
Use
with pages 136-140.
List the three reasons scientists found Rutherford's nuclear atomic model
to be fundamentally incomplete.
1.
2.
3.
Explain the relationship shown by the figure below. Use the following
terms: wavelength, frequency, amplitude, and speed.
!
Lonoer
\
wavelength ,,,r
J-
!
Shorter
wavelength
Lower frequency
tt
l<+l
o
Higher frequency
!
a
I
B
g
(,
=
I
.9
o
o
U
Science Notebook. Electrons in Atoms
7?
1 Light and Quantized
Use
with pages 139-140.
Energy (continued)
,
:ri:'.
r
:'
:
-
State the relationship between the energy and the frequency
of electromagnetic radiation'
Solve
Read Example Problem 1 in
yourtext.
Problem
Radio waves are used to transmit information on various channels. What
is the
wavelength of a radio wave having the frequency of 5.40x 1010 Hz?
1. Analyze the Problem
Known: v:
and c =
\_
Unknown: n You know that because radio waves are part of the electromaqnetic
spectrum, their speed, frequency, and wavelength are related by the
formula c = Xv.
2.
Solve for the Unknown
Solve the equation relating the speed, frequency, and wavelength
an electromagnetic wave for wavelength (X).
of
lfc:Xv,thenX:
Substitute c and the frequency of the radio wave, u, into the equation.
Note that hertz is equivalent to l/s or s
1.
\Divide the values to determine wavelength,
required.
€
tl=,
@
a
*
\
and cancel units
as
=
i
A
Science Notebook. Electrons in Atoms
74
1 Light and Quantized Energy (continued)
Use
with pages 140-143.
3.
Evaluate the Answer
The answer is correctly expressed in a unit of
Both of the known values in the problem are expressed with
significant figures, so the answer must
have
significant
figures.
ldentify two facts the wave model of light failed to explain.
1.
2.
Describe Planck's quantum concept by completing the foltrowing
statement.
The quantum concept concludes that matter can gain or lose
called
minimum amount of energy that can be
only in small, specific amounts
.
A quantum is the
or
by an atom.
c
Explain why the color of heated objects changes with
U
I
temperature.
B
s
IJ
E
o
.9
d
Describe the photoelectric effect.
Science Notebook. Electrons in Atoms
75
1 Light and Quantized
Use
with pages 142-i45.
Energy (continued)
Compare and contrast Einstein's equation with Planck's equation by
completing the followi ng sentence.
Planck's equation,
,
demonstrates mathematically that the
energy of a quantum is related to the
of the emitted
radiation. Einstein went further by explaining that, in addition to its
wavelike characteristics, a beam of light can be thought of as a stream of
called
Contrast the continuous electromagnetic spectra and the atomic
emission spectra.
Sffi
fT? Explain
how an emission spectrum is produced.
o
=.
@
@
=
6r
f
=
h
4
a
fanwiffiw$ l{"i
8.
Compare the dual nature of light.
Science Notebook. Electrons in Atoms
76
1 Light and Quantized Energy (continued)
9. Describe the phenomena
that can be explained only by the particle model of light.
10. Compare and contrast continuous spectrum and emission spectrum.
1
1. Assess
Employ quantum theory to assess the amount of energy that matter gains and
loses.
12. Discuss the way in which
Einstein utilized Planckt quantum concept to explain the
photoelectric effect.
13. Calculate Heating
.A
!
235 g of water from22.6'Cto94.4"C in a microwave oven requires
7.06 x 104J of energy. lf the microwave frequency is 2.88 x 1010 s-l, how many quanta
are required to supply the 7.06 x 104 )?
=
T
tg
I
E
o
.g
I tq. lnterpret S<ientific lllustrations Use Figure 5 and your knowledge of
electromagnetic radiation to match the numbered items with the lettered items.The
numbered items may be used more than once or not at all.
a. longest
wavelength
frequency
c. greatest energy
b. highest
1. gamma ray
2. infrared wave
3. radio waves
Science Notebook. Electrons in Atoms
77
5 Electrons in Atoms
2 Quantum
Theory and the Atom
@:(rt,o(nl,o(ct
i1;-
;i.
"- - --
€
!E
:
Write the Main ldea for this lesson.
ffi*w:e+s
H****uuariY
atom
F*ma,s
Recallthe definition of the ReviewVocabulary term.
atom
e3+<affi,iLeRy
ground state
quantum number
Define each New Vocabulary term.
ground state
quarffum number
de Broglie equation
Heisenberg uncertainty
de Broglie equataon
principle
quantum mechanical
14
ei s enb erg un c ert
airrty Vrin ciple
modelof the atom
atomic orbital
principal quantum
quanfum mecnanical model of the atorn
(t
number
@
=.
principal energy level
energy sublevel
t
@
atomic orbital
=
6
prin ciV al quarftum numb er
principal energy level
energu sublevel
Science Notebook. Electrons in Atoms
78
d
€
I
=
m
q
2 Quantum
Use
Theory and the Atom (continued)
with pages 146-1 50.
Classify the characteristics of each series in hydrogent line spectrum,
I nclude the following information.
1.
Beginning orbit(s) and ending orbit
2.
Description of the spectral line
Balmer
Lyman
Paschen
1.
1.
1.
2.
2.
2.
,-;', .
Explain why different colors of light result from electron
behavior in the atom.
o
!u
I
'
Sequence de Broglie's process in developing his equation by completing
the following sentences.
g
=
@
1.
of
Whole
are allowed in a circular
orbit of fixed
o
and
both
2.
Light has
3.
Can particles of matter, including electrons, behave
4.
lf an electron
has
of fixed radius,
is allowed only certain possible
,
and
Science Notebook. Electrons in Atoms
79
like
?
and is restricted to circular orbits
the
wavelengths,
characteristics.
2 Quantum
Use
with pages
1
51
Theory and the Atom (continued)
-1 52.
Discuss how Heisenbergt principle influenced Schrodinger to develop
his wave equation.
#e"n*
ffi?
&ef
8Y? Compare and contrast Bohr's model and the quantum
Explain the Heisenberg uncertainty principle.
mechanical model.
#t-g ffi
Describe where electrons are located in an atom.
n
o
!
:.
@
@
=
o
ts
{
o
a
o
Science Notebook. Electrons in Atoms
80
2 Quantum
Use
Theory and the Atom (continued)
with pages 153-155.
ldentify four facts about atomic orbitals by completing the following
statements.
indicate the relative sizes and
1.
energies of atomic orbitals.
2.
The atom's major energy levels are called
3. Principal energy levels contain
in a principal
4. The number of
as n increases.
energy level
,. i-' , l
.
Explain the relationship between energy levels and sublevels.
Describe the shapes of s and p orbitals.
Compare and contrast the Bohr and quantum mechanical models of the atom.
o
!u
I
!g
1,
E
o
.E
U
:jlir-.:,ir
i1
I
15. Explain the reason, according to Bohr's atomic model, why atomic emission spectra
contain only certain frequencies of light.
Science Notebook. Electrons in Atoms
81
2
Quantum Theory and the Atom (continued)
16. Differentiate between the wavelength of visible light
and the wavelength of a moving
soccer ball.
17. Enumerate the sublevels contained in the hydrogen
What orbitals are related to each
s
atom's first four energy levels.
sublevel and each p sublevel?
18. Explain why the location of an electron in an atom is uncertain using the Heisenberg
uncertainty principle and de Broglie's wave-particle duality. How is the location of
electrons in atoms defined?
I9. Calculate
the information in Table 1 to calculate how many times larger the
hydrogen atom's seventh Bohr radius is than its first Bohr radius.
Use
o
!
@
=.
@
20. Compare and contrast
6
Bohr's model and the quantum mechanical model of the atom.
€
=
o
a.
o
5
Science Notebook. Electrons in Atoms
82
5 Electrons in Atoms
3
Electron Configuration
MAIN
@6(E)
IDEA
Write the Main ldea for this lesson.
RErsrew
Vc**suLenY
Recallthe definition of the ReviewVocabulary term.
electron
electron
Naw Vccn&uLAftY
Define each New Vocabulary term.
electron configuration
eledron cor*iguration
aufbau principle
Pauli exclusion principle
autbau principle
Hund's rule
valence electron
electron-dot structu re
o
Pauli exclusi on prin ciple
fiund's rule
T
=
=
@
E
.9
o
valence eleclron
eledron-dof Elructure
Science Notebook. Electrons in Atoms
83
3
Electron Configuration (continued)
Use
with pages 156-161.
Organize information about electron configurations by completing the
following outline.
Electron configuration
1. Ground-state
A.
is
electron configurations
Three rules define how electrons can be arranged in an atom's
orbitals:
1.
2.
3.
State the three rules that define how electrons are arranged
in atoms.
B.
The
methods for representing an atom's
electron config u ration
1.
Orbitaldiagrams
a.
b.
An empty box represents
an
A box containing a single up arrow represents an
6
with
c.
S
orbital q
fi
A box containing both up and down arrows represents
il
a i
=
fr
r
d.
Each box is labeleO
*itf'
and
I
tf,.
associated with the orbital.
Explain how to write the noble-gas notation for an element.
What is the noble-gas notation for calcium?
Science Notebook. Electrons in Atoms
84
3.
3
Electron Configuration (continued)
Use
with page
162.
Solve
Read Example Problem 3 in your text.
Problem
Ruthenium (Ru) is commonly used in the manufacture of platinum alloys.
What is the ground-state electron configuration for an atom of
ruthenium?
1. Analyze the Problem
Known:
Unknown:
Determine the number of additional electrons a ruthenium atom has
compared to the nearest preceding noble gas, and then write out
rutheniu m's electron configuration.
2.
Solve for the Unknown
From the periodic table, ruthenium's atomic number is determined to
be
Thus a ruthenium atom
.
contains
electrons. The noble gas
preceding ruthenium is krypton (Kr), which has an atomic number of
36. Represent ruthenium's first 36 electrons using the chemical
symbolfor krypton written inside brackets.
The first 36 electrons have filled out the 1s,2s,2p,3s, 3p,4s, 3d and 4p
sublevels. The
remaining
electrons of ruthenium's configuration
need to be written out.Thus, the
remaining
electrons
fillthe
orbitals.
!
I
I
Using the maximum number of electrons that can fill each orbital,
E
write out the electron configuration.
@
o
3.
Evaluate the Answer
All
electrons in a ruthenium atom have been accounted for.The
correct preceding noble
gas
notation, and the order of orbital filling for
correct.
Science Notebook. Electrons in Atoms
85
has been used in the
the
is
3
Electron Configuration (continued)
exclusion principle, the aufbau principle, and Hund's rule to write out
the electron configuration and draw the orbital diagram for each of the following
elements.
29. Apply the Pauli
a. silicon
30. Define
d. krypton
c. calcium
b. fluorine
valence electron.
and describe the sequence in which ten electrons occupy the five orbitals
related to an atom's d sublevel.
31. lllustrate
o
E
32. Extend the aufbau
sequence through an element that has not yet been identified, but
whose atoms would completely fill 7p orbitals. How many electrons would such an
atom have? Write its electron configuration using noble-gas notation for the previous
noble gas, radon.
@
@
=
a
:
E
d
=
a
o
33. lnterpret Scientific Illustrations
Which is the correct electron-dot structure for an
atom of selenium? Explain.
d..s.
Science Notebook. Electrons in Atoms
86