Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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I am really sorry it’s so long but there are quite a few diagrams and a lot of short bullet points! But good
luck and may the odds be ever in your favor! Also: DO NOT IGNORE THE SIDE NOTES AT THE END OF
THIS STUDY GUIDE!!!
I. The Science of Paint
Vocabulary:
o Element:
Purely one type of atom
Can be single atoms or molecules
Ex) Kr, Ar, Ne, , ect.
o Mixture:
Composed of two or more components in proportions that can vary
from sample to sample.
Ex) salt water, tea with sugar, kool-aid
o Suspension: Heterogeneous mixture that has particles large enough that they
will settle if allowed to sit
Ex) Mud
o Compound:
Made up of more than one type of atom
Fixed, definite proportions (the subscripts)
Ex) , NaCl, ect.
o Solution:
Homogenous mixture of a solute and solvent
Aqueous Solution: A solution where water is the solvent.
o Solute:
The minority compound of a mixture
What is dissolved
o Solvent:
Majority component of a mixture
What does the dissolving
o Solubility:
The amount of a substance that will dissolve in a given amount of
solvent
Based on the strength of the interaction between the different particles
The stronger the interactions, the more the two particles will interact.
o Absorption: The process or action by which one thing absorbs or is absorbed by
another.
o Emission: The production and discharge of something, especially gas or
radiation.
What Paint is & how it works:
o The two parts of paint are (1) pigments and (2) the liquid/paint vehicle
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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Pigments:
What gives the paint its color
Can be organic (made mostly of carbon) or a metallic compound
Liquid/Paint Vehicle:
The part that allows you to spread the paint around
Made up of many different things (water or oil based)
o As the paint dries, the liquid evaporates leaving behind the pigment and other
things
How salt changed the painting:
o The texture that the salt created on the paintings was due to a property called
solubility
o Solubility: see definitions
o Salt is very soluble in water, so the salt and water particles interact very strongly
with each other.
o The interaction between the salt and water pushed the pigment particles out of
the watercolor mixture.
o The lack of pigment creates the white spots on the paintings.
II. Electromagnetic Spectrum and Light
See Attachment 1 for parts of EM Spectrum, everyday uses, ranks by energy, ranks by
wavelength, ranks by frequency
Wave-particle Duality
o Double slit experiment (book page 301-302)
Diffraction pattern instead of dots
Light and dark spots showing interference
Conclusion: light is a wave
o Photoelectric effect (book page 303)
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To get an electron to leave you must provide it energy
If light was a wave, you could simply point a light (no matter how bright)
at something and eventually an electron would leave.
Two important observations
No lag time
Threshold frequency (energy)
Conclusion: light is a particle.
o Actual Conclusion
EM radiation displays the properties of both a wave and a particle.
Called wave-particle duality
The evidence:
Double-slit experiment: wave behavior
Interference and diffraction
Photoelectric effect: particle behavior
Light energy comes in packets
Parts of a Wave (define and know the units), Calculations, and Conversions
o label the diagram using your notes
Amplitude
Wavelength ( ) : meters
Frequency (v): hertz (Hz) or
Energy of a single proton: E=hv
Einstein
h= 6.626*10^-34 J*s (blanck’s constant)
v- frequency
E (energy) in units of joules
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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E=hc/ (wavelength substitution)
o Conversion
C=
C= 3*10^8 m/s (speed of light)
III. Emission of Light and Atomic Models (Ohio State University Handout)
Atoms can absorb energy in various forms (heat, electrical, radiant-radiation or light)and
subsequently emit photons
The instrument used to view line spectra is a spectroscope
Physical Models
o Sometimes scientists construct physical models that represents an object on a
different scale
Conceptual models
o Allows one to make predictions and makes sense of a complex system
o Atomic models are conceptual. They aim to communicate different
characteristics and make predictions for something that cannot be directly
observed.
Dalton’s Billiard Ball Model
o What is the atom like? A hard sphere
o What happens when photons interact with the atom in this model? The photons
deflect off of the atom.
o For this model is there an emission spectrum? Nope
o Why do you think the Dalton model doesn’t include electrons?
The smallest particle in Dalton’s model is the atom, which is indivisible.
It doesn’t include sub-atomic particles like electrons
Electrons were discovered by J.J. Thomson 50 years after Dalton’s
death.
Thomson’s Plum Pudding Model
o “Jell-O with fruit”
o What happens when photons interact with the atom in this model?
The electron changes position when struck by the photon
All emitted photons have the same energy
o Is the resulting emission spectrum right? Nope
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Rutherford’s Classical Solar System Model
o What is the atom like?
There is a nucleus containing protons
There is an electron circling the nucleus, like a planet around the sun.
o What is the shortcoming of the solar system model? The atom isn’t stable. The
electron loses energy, spirals into the nucleus and the atom is destroyed. In this
model atoms shouldn’t exist.
Bohr’s Model
o What is the atom like?
There is a nucleus where the proton resides.
There is an electron in motion in a circular orbit.
There are several possible orbits the electron may follow.
o What happens when photons interact with the atom? Does the electron move?
When photons hit the electron, they bump the electron to another, higher,
energy level.
o Is the resulting emission spectrum right? The spectral lines are similar but there
are more infrared radiation (IR) lines, so nope.
o More information in the packet
The de Broglie Model
o What is the atom like? How does it include waves?
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The proton (in the nucleus) is in the center of the atom
The electron is a wave
The electron is in motion
o What happens when photons interact with the atom? No change from the Bohr
model, when light hits the atom the electron gets promotes.
o Is the emission spectrum right? Same as the Bohr model, so nope. The spectrum
still looks the same because all he did was change the electron to a wave.
The Schrodinger Model
o What is the atom like?
There is a nucleus.
The position of the electron is represented in an ambiguous manner.
Different areas are shaded.
o What happens when the photons interact with the atom? The electron cloud
moves.
o Energy levels sketch: see packet (I don’t feel like putting it in here right now)
o Is the emission spectrum right? Yes!
o He added subshells and orbitals to the previous model.
What statement is true regarding eh emission of a photon from a hydrogen atom? The
emission of photons is an exothermic process so the is negative.
IV. Introduction to Spectroscopy
Vocabulary
o Spectroscopy: the study of the interaction between EM radiation and matter.
o Absorption Spectroscopy: Measures the light that is absorbed by the analyte.
o Emission Spectroscopy: Measures the light that is emitted by the analyte.
o Absorption Spectrum: see diagram and notes page 7
o Emission Spectrum: see diagram and notes page 7
o Line Spectra: see notes page
o IR Spectroscopy: see notes page 7
o Mass Spectroscopy: see notes pages 7 and 8
Importance of & how it relates to conceptual models
o Spectroscopy provides the experimental evidence for the structure of the atom.
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Everyday Examples
o Neon Signs
o Fireworks
Absorption vs. Emission Spectroscopy
o Absorption Spectroscopy: see vocabulary
o Emission Spectroscopy: see vocabulary
o Absorption is most often used for lab analytical techniques (esp. quantitative)
o Emission most often is used to identify (qualitative)
o Mostly interchangeable though
Obtaining the different Spectra
Spectra: Uses in Astronomy
o Used to tell what elements make up a far off galaxy based on which ones we
see. These spectra are then analyzed by comparing the spectra we observed to
that of other elements. We can do this because line spectra are unique for every
element.
o There are others, I just don’t have notes on them… sorry!
Line Spectra
o Evidence for the quantum model (not continuous) - electrons are only in certain
places or energies.
o Shot radiation (UV and visible) at the atom
o Only certain wavelengths were absorbed and emitted
o Unique for every element
o Can be sued quantitatively as well.
Information Provided by IR Spectroscopy
o Infrared radiation doesn’t have enough energy to excite electrons
o Causes bonds in molecules to vibrate, bend, and rotate
o Bonds have unique resonant frequencies which can be used to identify their
presence.
o Helps to identify organic molecules
Mass Spectroscopy
o Mass spectroscopy disproved the theory that all atoms of an element are
identical.
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o Direct evidence of isotopes
o Can identify elements/isotopes from mass spec
o Can estimate that average atomic mass from a mass spec
(relative abundance)* (isotope 1 mass) + (relative abundance)*(isotope
2 mass) ect.
Relative abundance: how common it is, how much of it is there?
o Practice Problems
Page 76 Question 15 (completed in class)
Page 81 Question 71 and 73 (in class) see ATT. 2
Page 81 Question 75 (completed in class)
V. UV-Vis Absorbance Spectroscopy (lab)
Beer’s law
o Relates concentration of a chemical species in a solution and the absorbance of
that solution
o A= Ebc
o A- absorbance
Measured by spectrometer
Compares light entering sample to the light that made it through your
sample
o E- molar absorptive constant (L*cm /mol)
o Unique for every element and wavelength
o b- path length (cm)
(bulb) (cuvette) (detector)
pathlength: distance light travels through solution (which would be the
length of the cuvette in this diagram)
o c- concentration (mol/L)
o An increase in the path length or concentration would increase the absorbance
because there is a direct relationship between those variables and the
absorption.
Path length: you are increasing the distance where the light can be
absorbed therefore the absorbance would be larger if you increased it.
Concentration: the light can’t pass through the substance as easily, aka
it is absorbed, because there are more molecules, therefore the
absorbance goes up if the concentration does.
Darker color= more concentrated= more absorbance
Linear relationship between A and c
Pre-Lab Questions:
o Why do we want to use a particular wavelength when determining the
absorption of a particular chemical species? Is it important to measure
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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absorbance for all wavelengths from 400 to 700 nm? (aka on objectives list: how
taking a scan of a solution can be used in lab & why we used a single wavelength
to measure the absorption of a particular chemical species )
We want to only measure the absorbance of the metal with no
impurities. It’s important to measure absorbance for all wavelengths
that way we know what the particular wavelength is.
By measuring one wavelength, we can measure just one chemical
species, even if it’s in a mixture
We must first determine which wavelength to measure.
o If you know the molar absorptivity of copper sulfate at 630 nm, explain how you
could determine a wavelength where the molar absorptivity is half of that
simply by examining the absorption spectrum.
o You would just look at the graph and follow it until you get to 0.5 on the
absorptivity side.
Serial Dilutions
o Like step 4 of the lab:
o Formula:
o Formula derived from:
o Example calculation: see your lab! (either step 4 or Data Question 2)
Calibration Plot (these notes are based on the post-lab problem on the back of the lab
handout, also can be seen below)
o Construction
o y-intercept: Closeness to zero
o R^2- precision, how well does your trend line fit your data, best fit is 1
o Linear relationship between A and c
o Best fit line- points may not be perfect, it’s the line that fits the points the best,
pretty self explanatory
Error analysis
o Going back to what the y-intercept and R^2 show and based on the post-lab
assessment…
R^2= 0.995, which means their data is precise because the trend line fits
the data well (the data points are actually on the line).
Y-intercept= -0.005494, is extremely close to zero, which means, using
beer’s law, that is a good model for that data.
Calculation
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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= 2.296 g CuSO4
How Spectrometer works
o The light goes through the substance in the cuvettte and the light that is not
absorbed by the substance goes to the detector which shows the absorbance.
(bulb) (cuvette) (detector)
VI. ChemActivity 3-6
ChemActivity 3: Coulombic PE (potential Energy)
o Model 1: Two Charged Particles Separated by a Distance “d”
Notes:
The potential energy (V) of two stationary charged particles is
given by the equation listed below, where q1 and q2 are the
charge on the particles and d is the separation of the particles
(in pm) and k is a positive-valued proportionality constant.
1pm= 10^-12 m
o CTQ’s
1. Assuming that q1 and q2 remain constant, what happens to the
magnitude of V if the separation, d, is increased? Smaller, decreases
2. If the two particles are separated by an infinite distance (that is d=
infinity), what is the value of v? Approaches/is zero
3. If d is finite, and the particles have the same charge (that is q1=q2), is
V>0 or is V<0? Explain your answer. V>0, because the number must be
positive.
4. If q or an electron is -1…
What is q for a proton? 1+
What is q for a neutron? 0
What is q for the nucleus of a C atom? 6+
5. Recall that a H atom consists of a proton as the nucleus and an
electron outside of the nucleus. Is the PE, V, of a H atom a positive or
negative number? Explain. Negative because a positive times a negative
must be negative.
0.2877mol 0.05 L 159.62 g CuSO4
L 1 mol. CuSO4
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
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The PE of the interaction between a proton and electron will
always be negative.
o Model 2: IE (ionization energy)
Notes:
The IE is the amount of energy needed to remove an electron
from an atoms and move it infinitely far way.
IE is usually measure in Joules
o CTQ’s (see table 1 pg 18, in packet for the table references)
6. Do you expect the PE of the hypothetical atoms in Table 1 to be
positive or negative numbers? Explain. Negative, because the opposite
charges cause negative numbers.
7. Without using a calculator, predict what trend (if any) you expect for
the values of V for these hypothetical atoms. From A to Z the V will
increase in magnitude or get more negative.
8. Calculate the Potential energies of the hypothetical atoms to
complete table 1. Use the value k= 2.31*10^-16 J*pm.
Just use the PE equation
9. What is the relationship between IE and V for these hypothetical
atoms? They are directly proportional, but opposite in sign.
10. Which of the following systems will have the large IE? Explain.
(a) An electron at a distance of 500pm from a nucleus with a charge +2
(b) An electron at a distance of 700pm from a nucleus with a charge +2
(a) would be the correct answer because it is close to the nucleus,
therefore harder to remove.
o 11. Which of the following system will have the larger IE? Explain.
(a) An electron at a distance d1 from a nucleus with a charge +2
(b) An electron at a distance d1 from a nucleus with a charge +1
(a) because it has a stronger attractive force
o 12. How many times is the larger of the two IEs from CQT 11? Show your work
so the second is two times larger.
o 13. Consider a H atom and a He ion, He+. Which of these do you expect to have
the larger IE? Explain. He+ because it has more protons for the same number of
electrons, it has a higher charge for the same distance.
ChemActivity 4: The Shell Model (I) (ok so I got lazy and am just typing up notes you
would need for the objectives list… sorry!)
o Objective 1: Explain how experimental ionization energies prove the existence
of electron shells
The numbers for the ionization energies drop once you start a new row
on the periodic table. Based on the first couple values you would expect
the values to continue to increase but actually they go down then back
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up. Which tells us that the distance increases, therefore proving the
existence of electron shells.
o Objective 2: be able to use the CPE equation to rationalize/explain changes in IE
data
The distance, when you add the second electron shell increase,
therefore the IE would go down. However as you get a larger charge
with the same distance (the 2nd shell) you see an increase in the IE. This
is based on the direct relationship between charge and IE and the
indirect relationship between distance and IE.
o Objective 3: Definition
Cation: a positively charges species
Ionization Energy: the minimum energy required to remove an electron
from a gaseous atom of that element.
First Ionization Energy: The energy required to remove the outmost/
electron from the atom. Corresponds to the smallest amount of energy
that a bombarding electron needs to be able to knock off one of the
atom’s electrons.
Shell: ummm I don’t really know how to explain it in simplistic terms so
it’s um a shell.
ChemActivity 5: The Shell Model (II)
o Effect of core electrons on valence electrons interaction with the nucleus
Valence Electrons: the electrons in the outermost shell of an atom.
Core Electrons: Electrons in shells closer to the nucleus.
Direct Quote from Packet: “Of particular interest is the repulsion of the
valence electron by the two inner-shell electrons [for Li atom]. This
dramatically decreases the overall force of attraction pulling the valence
electron toward the nucleus. (AKA electron shielding)
The outer-shell valence electrons experience the charge of the core
rather than the full charge of the nucleus.
o Core Charge Calculations
Number of protons – number of core electrons = core charge
The nucleus plus the inner shells of electrons constitute the core of the
atom and the net overall charge on the core is called the core charge.
o Difference between core charge and effective nuclear charge (
Core charge is a simplified version of and doesn’t take into account
inner-shell electron repulsion and the movement of electrons.
The overall resulting charge action on a valence shell electron is known
as the effective nuclear charge, and it is generally less than the core
charge.
o Relationship of an atom’s position on the periodic table with core charge,
number of valence electrons, and valence shell.
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Core Charge
Elements in the same group have the same core charge.
Core charge increases as you go across a period.
Number of Valence Electrons
Elements in the same group have the same number of valence
electrons.
The number of valence electrons increases as you go across a
period.
Valence Shell
Elements in the same period have the same size valence shell.
The size of the valence shell (i.e. the distance the valence shell is
from the nucleus) increases as you go down a group.
VII. Periodic Table Basics
Definitions
o Nucleus: The central part of the atom containing neutrons and protons.
o Proton: A positively charged particle in the atom which doesn’t change and
therefore can be used to ID an element.
o Neutron: A neutral particle in the atom which changes and therefore cannot be
used to ID an element.
o Electron: A negatively charged particle in the atom which changes and therefore
cannot be used to ID an element.
o Atomic Mass: The mass of the nucleus.
o Atomic Number: Equal to the number of protons an element has.
o Ion: A charged atom.
o Anion: A negatively charged atom which has gained electrons.
o Cation: A positively charged atom which has lost electrons.
o Isotope: An atom with a different number of neutrons, and therefore a
different atomic mass than the neutral version of the same element.
Periodic Table: Know Location
o Common properties of metals
Good conductors of electricity
Good conductors of heat
Ductile: ability to be drawn into a thin wire
Malleable: Bendable
Shiny (sometimes)
Lose electrons
o Common properties of non-metals (basically just the opposite of metals)
Poor conductors of electricity
Poor conductors of heat
Gain electrons
o Main Group Elements
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Main-group elements: the former “A” group elements of the periodic
table.
Alkali Metals- group 1
Alkaline Earth Metals- group 2
Halogens- group 7
Noble Gases- group 8
o Transition metals/elements: groups 3-12
Less predictable properties.
o Metals: Right of stair step
o Non-metals: left of stair step
o Metalloids: directly on the stair step
Properties of metals and non-metals
Many are semi-conductors (an element that has conductivity that
changes based on temperature- controllable conductivity)
o Lanthanides: Period 6 (#57-71)
o Actinides: Period 7 (#89-103)
Other Objective Notes
o Chemical Symbol:
Element Abbreviation
Atomic Mass
Atomic Number
o Isotope Symbol: Carbon-14
Element
Mass
o The atomic masses found on the periodic table are always decimals because
they are a combination of all of the common isotope masses more or less
averaged.
Determine. . . How you find it. . . Example. . . Li (Lithium)
Protons Atomic number 3 Neutrons Mass (rounded) – atomic number 4 Electrons If neutral, equal to atomic number 3 Metal vs. Non- Metal Left or right of stair step Metal Group name Know the names!!!! Alkali Metal
VIII. Electronic Structure of Atoms
Definitions:
o Valence Electrons: the electrons in the outermost shell of an atom. Do
participate in chemical reactions (s and p are the only sublevels we consider
valence for now)
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o Core Electrons: Electrons in shells closer to the nucleus. Electrons that don’t
participate in chemical reactions.
Objective List Notes
o The electrons structure of an atom determine its chemical properties (how it
reacts)
o Energy Levels/shells = PERIOD
o Sublevels/subshells = BLOCK (see below)
“s” block: groups 1 and 2
“d” block: groups 3-12
“p” block: groups 13-18
“f” block: Lanthanides {Period 6 (#57-71)} and Actinides {Period 7 (#89-
103)}
o Sublevel Information
“s”: holds 2 electrons and contains 1 orbital
“p”: holds 6 electrons and contains 3 orbitals
“d”: holds 10 electrons and contains 5 orbitals
“f”: holds 14 electrons and contains 7 orbitals
o Each orbital can hold 2 electrons (duh)
o Electron Configuration
Long-hand:
Determine the number of electrons in the atom
Locate the element on periodic table to find the ending energy
level and subshell
You must fill all energy/sub-levels before moving to the next
Use periods and blocks to know the filling order.
Short-hand:
Find atom, go up 1 period from the atom and all the way to the
right/end of the period
Write noble gas you found in brackets
Start writing electron configuration as usual from beginning of
the period the atom is found in.
o Noble gases end with completely full energy levels and subshells. The fact that
they have full shells makes them very stable. All elements want to be stable so
they attempt to add or lose electrons until they have full shells.
o Since noble gases are full we can use them to represent the core electrons of
other atoms.
o Elements in the same group have the same number of valence electrons and the
same chemical properties.
Predicting Ion Charges
o Knowing which electrons are care and which are valence electrons allows you
to predict the charge of the ion the atom will form
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o Main group elements follow the octet rule:
Octet rule: full s and p subshells are most stable, so atoms will gain
electrons until they have 8 valence electrons
Elements/atoms in the same group have the same number of valence
electrons therefore all atoms in a main group will form ions of the same
charge
If an atom has 0-3 VEs, the atom will lose electrons (positive charge) to
satisfy the octet rule (going backwards to previous noble gas)
If an atom has 5-7 VEs the atom will gain electrons (negative charge) to
satisfy the octet rule (going forwards to the closest noble gas)
IX. ChemActivity 8-11
ChemActivity 8
o How electron impact method works
You shoot an electron at an atom and an electron from the highest
energy level (the electron that can be most easily removed) comes off.
Also see definitions- electron impact method.
o Information obtained from electron Impact method
These experiments give a value for the IE of the electron that is most
easily removed from the atom, i.e. the IE for an electron in the highest
occupied energy level.
o Information obtained from photoelectron spectroscopy
Provides information on all occupied energy levels of an atom (the
ionizations energies of all electrons in an atom).
o PES contribution to model of atom
The idea of orbitals
o Theory of electron ejection during PES experiment
Each atom will eject only one electron, but every electron in each atom
has an (approximately) equal chance of being ejected.
o Diagram of PES
The size of the peak in the spectrum is determined by the relative
number of electrons with a given IE.
o What’s responsible for the position of a peak on the x-axis: Ionization energy
o What’s responsible for peak height in PES spectrum: Relative number of
electrons
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o Importance of the word “relative” on the y-axis: CTQ 12
(a) Explain why it is not possible to determine if the “unknown” atom is
H or He
It’s a relative scale and we have nothing to compare it to.
(b) Explain why the “unknown” atom cannot be Li.
Li would need 2 peaks because it has 2 energy levels. (NOTE:
this was prior to the CA where we found out that it is actually
the sublevels that determine the number of peaks).
o The word relative is important because it tells us that we need to be comparing
two things in order to know the number of electrons.
o Definitions
Quantized: only certain discrete energy levels should be found.
Electron Impact method: Atoms in the gas phase are bombarded with
fast-moving electrons.
Photoelectrons: Electrons obtained from photoelectron spectroscopy
Photoelectron spectrophotometer: the device that measures the kinetic
energy of the electrons.
Photoelectron spectrum: how the results of a photoelectron
spectroscopy experiments are conveniently presented.
ChemActivity 9
o Why lack of units on y-axis of PES is acceptable
It is a relative number, also its just the relative number of electrons
therefore electrons would be the “units” but that isn’t really a unit so it
is acceptable to have no units.
o Interpretation of PES
Number of energy levels: how many scale changes (i.e. large gaps in IEs
there are)
Number of sublevels: number of peaks
Number of electrons per sublevel: First, we know that the first sublevel,
s, only has 2 electrons, thus the first peak must represent two electrons.
Then compare the other peaks to the first one.
Relative energies of the peaks:
If energies are far apart: different energy level
If energy levels are close together: same energy level, different
sublevel.
o Predicting PES for given element
Number of peaks is determined by the sublevels in an atom
Relative height of peaks depends on how many electrons are in each
sublevel.
o Energy level diagram (exercise 3)
Sketch the energy level diagram for Be and for C (as in Model 2).
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Be:
C:
ChemActivity 10
o Interpret IE data into electron configurations
From Table 1 ChemActivity 10 page 44:
Gives you the energy level and sublevel, and the element
You can compare the ionization energy values to determine the
possible number of electrons.
From a PES diagram:
Number of peaks = number of sub shells
Number of Scale gaps = number of energy levels
Relative heights of peaks = number of electrons per sub shell
o What experiment is responsible for producing IE data?
PES- Photoelectron Spectroscopy
ChemActivity 11
o Objective 1: explain how PES determined the d subshell is filled after the s
subshell.
It has (1) a higher ionization energy than the s and (2) when looking at a
graph, comes before the next s subshell.
o Objective 2: explain how PES determined that the s subshell electrons are
removed first when a transition metal ionizes.
They have the lowest ionization energy and, even though there may be
a d or an f subshell in the atom, the furthest shell.
o Objective 3: Know how the blocks of the periodic table are related to the filling
order of the periodic table.
X. Atomic Trends
Definitions:
o Core Charge: The effective nuclear charge experienced by an outer shell
electron. In other words, core charge is an expression of the attractive force
experienced by the valence electrons to the core of an atom which takes into
account the shielding effect of core electrons.
o Atomic Radius: The distance from the nucleus to the outermost electron.
o Ionic Radius: The distance from the nucleus to the outermost electron.
o Ionization Energy: The minimum energy required to remove an electron from a
gaseous atom of that element.
o First Ionization Energy: The amount of energy required to remove the first
electron from the atom (outermost)
o Electronegativity: How much an atom attracts electrons/ “wants electrons”
o Reactivity: How easily an atom exchanges electrons (loss or gain).
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
19 Made By Ashley Thomas
Atomic radius/size
o Increases as you get farther left (across a period) and farther down a group
Ionic radius/size
o Increases as you get farther left (across a period) and farther down a group.
1st Ionization Energy
o Increases as you get father right (across a period) and farther up a group
Electronegativity= Electron Affinity
o Increases as you get farther right (across a period) and farther up a group
Metal Reactivity
o Increases as you get farther left (across a period) and farther down a group.
o Depends on the ionization energy of the atom
Non-Metal Reactivity
o Increases as you get farther right (across a period) and farther up a group.
o Depends on the electronegativity of the atom.
XI. Quantum Numbers (no objectives list)
Principal Quantum Number (n)
o Energy level
o Indicates distance from the nucleus
o How to figure it out: the period the element is in
Ex) (2s)= 2
o Options available (what are the possible values): n=1, 2 . . . period of the
element
Ex) Ca: n=1,2,3,4
Orbital Angular Momentum Number (l)
o Sublevels
o Indicates the shape of the region
Spherical: s sublevel
Dumbbell: p sublevel
Double dumbbell Donut: d sublevel
Fancy: f sublevel
o How to figure it out: the sublevel from the electron configuration
o Options Available: l = 0, 1 . . . n-1
Ex) for n=2, what are the possible values of l? l= 0,1
Magnetic Quantum Number
o Orbitals (REMEMBER THEY ONLY HOLD 2 ELECTRONS!!!)
o Indicate the orientation of the region in space
o How to figure it out: atomic orbital diagram
o Options Available: = -l, . . . , +l
L=2, what are the possible values of = -2 -1 0 1 2
Spin Quantum Number (
Trimester 1 Honors Chemistry 2014-2015 Final Exam ** DO NOT ONLY RELY ON THIS STUDY GUIDE**
20 Made By Ashley Thomas
o When two electrons are in a magnetic field, they will align opposite of one
another. This is called the “spin”.
o The electrons within an orbital must have opposite spins to overcome their
repulsion.
o How to figure it out: two electrons in the same orbital have opposite spins, by
convention single electrons have a +1/2 spin
o Options Available: +1/2 (up arrow) OR -1/2 (down arrow)
Atomic Orbital Diagram:
o Visual representation of quantum numbers of electron configuration
o How to:
(1) Write electron configuration
(2) Draw boxes/lines representing orbitals for entire electron
configuration.
(3) Label boxes/lines with values.
(4) Place electrons (arrows) in the boxes/lines following the 3 rules:
Pauli Exclusion Principal: No two electrons can have the same 4
quantum numbers
Can share 1,2, or 3 quantum numbers in common
Basically you can’t put two up arrows right next to each
other (on the same line or in the same box)
Aufbau Principal: Fill from lowest energy to highest energy
Hund’s Rule: Fill atomic orbitals in the way that results in the
lowest energy possible (aka the no pairing rule).
**PLEASE ALSO REFERENCE THE MID-TERM EXAM STUDY GUIDE AS IT HAS
MORE INFORMATION ABOUT THE FIRST COUPLE TOPICS ON THIS LIST
**Attachments: 1,2 (same attachments as mid-term study guide, I am not
reposting them under this study guide!)