Chemistry NYA Class Notes and Exercises Part 2

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College Chemistry NYA Class Notes and Exercises Part 2

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  • Email: [email protected]: f-228Phone: x311

    CHAMPLAIN COLLEGESAINT-LAMBERT

    GENERAL CHEMISTRY

    202-NYA-205

    Winter 2012

    Joel Robichaud

  • Course Outline

    nomenclature empirical & molecular formulas stoichiometry gas laws molarity

    UNIT 1:Basics

    UNIT 2:Atomic Theory

    history of atomic theory the Bohr atom the modern approach (quantum theory) quantum numbers electron configurations electron affinity

    UNIT 3:Periodicity &

    Chemical Reactions

    electron configuration & chemical properties of elements ionization energy atomic and ionic size electronegativity & electron affinity reactions of the main group elements writing molecular & net ionic equations

    UNIT 4:Chemical Bonding

    analysis of ionic & covalent bonding writing Lewis structures, resonance structures formal charges shapes of molecules bond angles bond polarity dipole moments hybridization theory orbital diagrams

    UNIT 5:Intermolecular Forces

    intermolecular forces intramolecularbonds dispersion forces, dipole-dipole forces hydrogen bonding relationship of melting & boiling point & solubility to intermolecular forcesclassification of substances

    UNIT 6:Liquids & Solutions

    properties of solids phase changes & phase diagrams physical properties of solutions concentration units colligative properties

  • give a brief overview of Thomsons experiments which led to the discovery of the electron. (2.2) give a brief overview of Rutherfords experiments which led to the discovery of the nucleus. (2.2) describe the mass & charge of each of the 3 fundamental subatomic particles: proton, electron & neutron. (2.2) explain the terms: atomic number, mass number, molar mass, atomic mass unit, isotope and atomic mass. (2.3, 3.2) describe the main features of the Rutherford model of the hydrogen atom. (class notes) define wavelength and frequency, and solve problems using the relationship . (7.1) identify the regions of the electromagnetic spectrum based on their frequencies and wavelengths. (7.1) explain the difference between continuous and line spectra. (7.3) describe the experimental setup to obtain the atomic spectrum of hydrogen. (class notes, emission experiment) give a brief outline of Plancks quantum theory and solve problems based on Plancks equation . (7.1) describe the Bohr model of the hydrogen atom. (7.3) use the Bohr equation to calculate the energy of the electron in a given Bohr orbit. (7.3, emission experiment) calculate E for the transition of an electron from one Bohr energy level to another. Also calculate and associated with these transitions. (7.3, emission experiment) recognize how calculations of E, and for energy transitions in the hydrogen atom enabled Bohr to explain the observed line spectrum. Also explain the importance of the Bohr model in the eventual development of atomic theory. (7.3, emission experiment) explain why, based on the Bohr model, hydrogen gives a line, not a continuous spectrum. (class notes, emission experiment) explain the shortcomings of the Rutherford model of the hydrogen atom. (class notes) explain the fundamental differences between the Bohr and Rutherford models of the hydrogen atom. (class notes) recognize the difference between emission and absorption spectra. (class notes)

    Unit II: Atomic Theory(Chang, Ch. 2, 7 & 8)

    Objectives:

  • recognize the difference between the ground state & excited states in the hydrogen atom spectrum. (class notes, emission experiment) calculate the ionization energy of the hydrogen atom (7.3, emission experiment) recognize that the Bohr model was only successful for one electron species, and explain the general limitations of the Bohr model. (7.3) outline the general features of the quantum mechanical model of the hydrogen atom based on the idea of the wavelike properties of matter. (7.5) outline the contribution of each of the following scientists to the development of the quantum mechanical model of the atom: Bohr (7.5), Heisenberg (7.5), Schrdinger (7.5), De Broglie (7.4), Pauli (7.8). list the quantum numbers: n, l, ml obtained by solving the Schrdinger wave equation for the electron in the hydrogen atom. Predict the allowable values of these quantum numbers. (7.6) explain the meaning of wave function and orbital. (7.5) relate the shapes of orbitals to the quantum number l. (7.6, 7.7) sketch the shapes of s and p orbitals. (7.7) recognize the shapes of d orbitals. (7.7) explain the meaning of electron spin and its relationship to the quantum number ms (7.6) apply the Pauli exclusion principle and Hunds rule to write the electron configuration and orbital filling (box) diagrams for multielectron atoms. (7.8) explain and apply the concept of effective nuclear charge. (7.9 & 8.3) identify the s, p, d, and f blocks in the periodic table. (7.9) relate the position of an element in the periodic table to its electron configuration. (7.9) know the anomalous electron configurations for first and second row transition metals. (7.9) explain and predict the trends in atomic radii. (8.3) predict whether an atom is para or diamagnetic based on its electron configuration. (7.8) give the allowable sets of the four quantum numbers (n, l, ml, ms ) for each electron in a given atom. (7.8)

    Continuation

  • 2.1 Atomic Theory(Chang, 2.1)

    Insight into the nature of matter:

    Aristotle (384-322 BC)

    Democritus (460-370 BC)

    Aristotle believed that matter was infinitely divisible.

    Democritus believed that matter was made up of tiny indivisible particles that he called atoms

    (from Greek, atomos, meaning indivisible).

    Atoms are the basic unit of matter.

    Atoms are extremely small (sheet of paper = 1 million atoms thick, 1 drop of water = 1022 atoms)

    Does matter have a basic/fundamental particle?

  • 2.1 Atomic Theory(Chang, 2.1)

    J. Dalton (1766-1844)

    John Dalton was an English scientist who created a hypothesis about the nature of matter.

    1. Elements are composed of extremely small particles called atoms.

    2. All atoms of a given element are identical (same size, mass & chemical properties). The atoms of one element are different from the atoms of all other element.

    3. Compounds are composed of atoms of more than one element. In any compound, the ratio of the #s of atoms of any 2 of the elements is an integer.

    4. A chemical reaction involves the separation, combination, or rearrangement of atoms; no creation or destruction of atoms (based on Lavoisiers Law of Conservation of Mass).

    Note: there was no attempt to describe the structure of the atom.

    Daltons atomic model (1808) is based on the following principles:

  • 2.2 Thomsons Experiment (Chang, 2.2)

    J.J. Thomson, an English physicist , postulated the existence of electrons based on his experiments with cathode ray tubes.

    J.J. Thomson (1856-1940)

    Using this experiment, Thomson determined

    the charge to mass ratio of an electron:

    e = -1.76 x 108 C/gm

    The Plum Pudding Model

    Thomson postulated that the atom was made of negatively charged electrons in a positively charged cloud

    (to maintain neutrality).

  • 2.3 The Millikan Experiment(Chang 2.2)

    The American physicist, Robert A. Millikan, determined the charge of an electron using the oil-drop experiment.

    By having the charge suspended in air, he was able to determine the charge on each oil drop. This led him to conclude that the charge of 1 electron was:

    -1.6022 x 10-19 C

    This allowed the determination of the mass of a single electron:

    mass of an electron = charge = -1.6022 x 10-19 C = 9.10 x 10-28 gcharge to mass -1.76 x 108 C/g

    R.A. Millikan (1868-1953)

  • 2.5 Rutherfords Experiment(Chang, 2.2)

    The New Zealand physicist, Ernest Rutherford, bombarded alpha particles (He2+, 7300 times the mass of an electron)through a gold foil, expecting them to go straight through.

    He proposed that the mass of the atom is concentrated in the nucleus.

    In separate experiments it was determined that the nucleus contains positively charged particles called protons (equal but opposite charge to the electron).

    E. Rutherford (1871-1937)

  • 2.6 Summary of Subatomic Particles

    The atom contains:

    Nucleus, which consists of:

    Electrons (same magnitude as proton but of negative charge).

    Charge

    Particle Mass (g) Coulomb Charge Unit

    Electron 9.10938 x 10-28 -1.6022 x 10-19 -1

    Proton 1.67262 x 10-24 +1.6022 x 10-19 +1

    Neutron 1.67493 x 10-24 0 0

    Protons (positively charge), Neutrons (almost same mass as proton but no charge).

    James Chadwick, a British physicist, discovered a new particle in the nucleus of the atom, the neutron

    (which comes from the latin neuter, which means neither one nor the other), which has no charge

    and holds the protons together.

    J. Chadwick (1891-1974)

  • 2.7 Atomic Number & Mass Number(Chang, 2.3, Textbook Problems: 2.14; 2.16; 2.18)

    Atomic Number (Z): the # of protons in the nucleus(the # on the periodic table).

    XA

    Z X is the symbol of the element.

    The type of atom is determined by the # of protons (if an element has a charge, it is due to a transfer of electrons and not of protons).

    In a neutral element:

    In a cation: # of protons > # of electrons,(the element lost electrons to become the ion).

    In an anion: # of protons < # of electrons,

    Mass Number (A): the # of protons plus the # of neutrons.

    (the element gained electrons to become the ion).

    # of electrons = # of protons.

  • 2.7.2 Exercises:

    1. Fill in the missing information:

    Element Symbol Z A # of

    neutrons

    # of

    electrons

    16 34

    Iron Fe 56

    17 16

    80 120

    Uranium U

    2. Determine the # of protons, neutrons & electrons for each of the following:

    a) K

    b) K+

    c) Al3-

  • 2.8 Isotopes(Chang, 2.3)

    Isotopes: substances with the same # of protons (hence, the same element), but different # of neutrons (hence, different masses).(from latin, iso = the same & topos = place: same place in the periodic table)

    Ex. H1

    1

    H1

    2

    H1

    3

    Hydrogen:(protium)

    Deuterium:

    Tritium:

    1 proton, 1 electron, 0 neutron

    1 proton, 1 electron, 1 neutron

    1 proton, 1 electron, 2 neutrons

    Note: Isotopes generally have the same chemical properties (same # of protons & electrons), but have different physical properties (different # of neutrons).

  • 2.9 Quantum Theory(Chang, 7.1, Textbook Problems: 7.4; 7.8; 7.10; 7.16; 7.18; 7.20; 7.22; 7.40; 7.42)

    Properties of atoms & molecules are not governedby the same physical laws as larger objects.

    The German physicist Max Planck discovered that atoms & molecules emit energy only in discrete energy called quanta (it was previously believed that any amount of energy could be emitted or released).

    Waves

    Wave: a vibrating disturbance by which energy is transmitted.

    Characterized by 3 factors:

    Wavelength, (in nm): distance between identical points on a successive wave.Frequency, ( in s-1 or Hz): # of waves that pass through a particular point in 1 second.Amplitude: vertical distance from the midline of a wave to the peak.

    M. Planck(1858-1947)

  • Continuation

    It is also possible to describe a wave by its speed ():

    = : wavelength (in nm) : frequency ( in s-1 or Hz)

  • 2.9.2 Electromagnetic Radiation

    Electromagnetic radiation: describes how energy in the form of radiation can be propagated through space as vibrating electric& magnetic fields.

    The speed of this waveis always the same& is equal to the speed of light:

    c = 2.9979 x 108 m/s

  • 2.9.1 Exercises:1. The wavelength of the green light from a traffic signal is centered at 522 nm.

    What is the frequency of this radiation?

    2. True or False?

    a) Blue light has a shorter wavelength than red light.

    b) X-rays have lower frequencies than radio waves.

    c) Microwaves have higher frequencies than gamma rays.

    d) Visible radiation composes the major portion of the electromagnetic spectrum.

  • Photoelectric EffectPlanck gave the name quantum to the smallest quantity of energy that can be

    emitted (or absorbed) in the form of electromagnetic radiation.

    E = hn = h c

    h is known as Plancks constant

    (h = 6.626 x 10-34 Js)

    Albert Einstein suggested that electromagnetic radiationbehaved not only as waves but also as matter.

    These particles of light are called photons and possess a mass(theory of the dual nature of light, it can act as a wave & as matter).

    E = mc2Ephoton = h c

    mphoton = E = hc/ = hc2 c2 c

    A. Einstein(1879-1955)

    Note: De Broglie postulated that matter can behave as waves as well (c would have to be changed for which is the speed of the object).

  • 2.9.2 Exercises:1. Sodium atoms have a characteristic yellow color when excited in a flame. The color comes from theemission of light of 589.0 nm. a)What is the frequency of this radiation? b) What is the change inenergy associated with this photon? Per mol of photons?

    2. What is the wavelength of an electron (m = 9.11 x 10-31 kg) travelling at 5.31 x 106 m/s? (1 J = 1 kg m2/s2)?

    Conclusions: Matter & energy are not so distinct.

    All matter shows particle properties as well as wave properties.

    Small matter (ex. photons) exhibit predominantly wave properties.

    Large matter (ex. baseball) exhibit predominantly particle properties.

  • 2.10 Bohrs Theory(Chang, 7.3, Textbook Problems: 7.24; 7.30; 7.32; 7.34)

    Emission SpectraWhen a substance is excited, either by heat or an electrical current, it will emit light.

    That is called the emission spectra of that substance.

    There are 2 types of emission spectra:

    Continuous spectrum:

    Line spectrum:

    Emission of all wavelength in the visible part of the electromagnetic spectrum(white light is a continuous spectrum),

    When passes through a prism it will look like a rainbow, the colors will be separated.

    Only specific wavelength are emitted,

    Characteristic of an element (like the fingerprint of that element).

  • Line Spectra

  • CVCV

    CV

    CV

    orbit 4

    orbit 3

    orbit 2

    orbit 1

    nucleus

    10.2 The Hydrogen Atom

    The Danish physicist Neils Bohr imagined that the atom was like a solar system with the electrons orbiting around the nucleus.

    He imagined that electrons were only allowed to exist on certain energy levels (i.e. the energy of the electron is quantized):

    En = -RH 1n2

    n is an integerRH equals 2.178 x 10

    -18 J (Ryedbergs constant)

    The most stable state is the ground state when n = 1.

    All other states, n = 2, 3, 4 ... are known as excited states(these are higher in energy than the excited state).

    N. Bohr (1885-1962)( )

  • When the hydrogen atom emits energy, the electron goes from a higher energy level to a lower energy level (i.e. the E is negative).

    The radius of an orbit is proportional to n: the larger the n, the larger the orbit, when the electron is farther from the nucleus, it is higher in energy.

    When the hydrogen atom gains energy, the electron goes from a lowerenergy level to a higher energy level (i.e. the E is positive).

    10.2 The Hydrogen Atom

  • The energy of the photons emitted is equal to the energy difference between 2 energy levels:

    The wavelengths emitted by hydrogen were separated in

    different series based on their nfinal.

    E = Efinal - EinitialE = (-RH) - (-RH)

    n2f n2

    i

    E = -RH 1 - 1n2f n

    2i

    Continuation...

    ( )

    The energy of an electron in another one electron species:

    En = -RH Z2

    n2(Z is the atomic #)

    Note: these calculations only workfor 1 electron species.

  • 10.2.1 Exercises:1. Calculate the energy corresponding to the n = 3 electronic state in the Bohr hydrogen atom.

    2. For the excitation from the n = 1 to the n = 3 electronic state in the hydrogen atom.a) Calculate the energy change.b) What is the wavelength of the electromagnetic radiation associated with this energy change?

    3. Give examples of one electron species:

  • 10.2.1 Exercises:4. What would be the energy and wavelength (in nm) of the light in the Lyman series when ni = 5?

    5. Calculate the shortest and longest wavelength (in nm) in the emission spectrum of the hydrogen atom for nf = 2 (Balmer series).

    6. Calculate the ionization of the hydrogen atom initially in the ground state.

  • 2.11 Quantum Mechanical Model & Quantum Numbers(Chang, 7.5 & 7.6, Textbook Problems: 7.56; 7.58; 7.60; 7.62; 7.64; 7.66)

    This model has a set of 4 quantum numbers (compared to 1 with the Bohr model) to described the position of the electron.

    Atoms emit or absorb energy when electrons move from one energy state to another.

    Electrons are found in orbitals (not orbits) which are 3 dimensional(these give the probability of finding the electron).

  • Principal Quantum Number (n):Can have a value from 1 to infinity; it is always an integer.

    It is the primary factor in determining the energy of an electron.

    It also determines the size of the orbital (average distance of the electron from the nucleus).

    The greater the n, the greater the energy & average distance.

    The primary quantum number is also referred to as a shell.

    2

    3

    1

    3

    1

    4

    5

    6

    7

    2

    3

    4

    5

    6

    7

    4

    5

    6

    5

    4

  • Angular Momentum Quantum Number ():Can have a value from 0 n 1, always whole numbers.

    Determines the shape of the orbitals.

    Is a secondary factor in determining the energy for polyelectronic atoms.

    The angular momentum quantum number is also referred to as subshell.

    Subshells are also referred to by letters according to their #:

    0 1 2 3 4 5

    Name s p d F G h

    (these letters refer to the shape)

  • Magnetic Quantum Number (m):

    Can have a value from - + .

    Describes the orientation in space of the orbital.

    The # of m possible is equal to 2 + 1.

    S (l = 0)

    d (l = 2)

    p (l = 1)

    f (l = 3)

  • When = 0, s

    When = 1, p

    When = 2, d

    Orbital Shapes:

  • One last quantum number...

    Superposing the Orbitals:

  • Electron Spin Quantum Number (ms):

    The value can be + or -.

    Describes the spin of the electron.

    Electrons act like tiny magnets and when then spin they create a magnetic field.

    There is 2 possible spinning motions for an electron (clockwise & counter-clockwise).

    S

    d

    p

    f

    -+

    + - Etc...

  • 2.11.2 Exercises:1. Determine the # of different orientations in space for the s, p, d & f orbitals.

    2. Which of the following sets of quantum numbers are allowed in the hydrogen atom? For each incorrect set, state why it is incorrect.a) n = 1, = 0, m = 1b) n = 2, = 2, m = 1c) n = 5, = 3, m = 2d) n = 6, = -2, m = 2e) n = 6, = 2, m = -2

    2.11.1 Exercise:

    1. For principal quantum level n = 4, determine the # of allowed subshells & give the name of each.

  • 2.11.3 Exercises:1. Which of the following sets of quantum #s are not allowed? For each incorrect set, state why it is

    incorrect.

    a) n = 3, = 3, m = 0, ms = -

    b) n = 4, = 3, m = 2, ms = -

    c) n = 4, = 1, m = 1, ms = +

    d) n = 2, = 1, m = -1, ms = -1

    e) n = 5, = -4, m = 2, ms = +

    f) n = 3, = 1, m = 2, ms = -

    g) n = 3, = 2, m = -1, ms = 1

    2. If each orbital can hold a maximum of two electrons (of opposite spin) how many electrons can each of the following subshells hold?

    a) 2s

    b) 5p

    c) 4f

    d) 3d

    e) 4d

  • 2.12 Atomic Orbitals(Chang, 7.7, Textbook Problems: 7.68; 7.70)

    The set of the 3 first quantum numbers describe the orbital.

    The last quantum number describes the electron.

    Energy of Orbitals

    Orbitals that have the same energy are called degenerate.

    For hydrogen:

    All orbitals with the same value of n have

    the same energy.

  • Because of the penetration effect:

    For polyelectronic atoms:

    Energy of Orbitals

    Ens < Enp < End < Enf

    (i.e. the 2s orbital is lower in energy than the 2p orbital)

    The penetration effect is caused by the other electrons which are shielding the nucleus(the system must account for the electron-electron repulsion).

  • 2.13 Electron Configuration(Chang, 7.8, Textbook Problems: 7.76; 7.78; 7.88; 7.90; 7.92; 7.96)

    The electron configuration describes how the electrons are distributedamong the various atomic orbitals.

    1s1

    It can also be described as an orbital box diagram:

    In the ground state, the electron configuration of hydrogen is:

    1s1

  • Aufbau Principle

    As protons are added one by one to create the various elements, so are electrons and these are placed in specific orbitals.

    Aufbau principle: electrons are added to the lowest energy orbitals first to create theground state of that element (from German, meaning building-up).

    The following chart describes which subshells are filled first:

  • Continuation

    The other way to determine the order by which subshells are filledis by following the periodic table:

  • Pauli Exclusion Principle

    The Austrian physicist Wolfgang Pauli established the principle that no two electrons can have the same set of 4 quantum numbers.

    Since the first 3 quantum numbers describe the orbital and the fourth quantum number can only have 2 values (+ & -):

    there can only be 2 electrons per orbital, each of opposite spin.

    1. Write the electron configuration and box diagram for the following atoms:

    a) H

    b) He

    c) Li

    d) Be

    e) B

    2.13.1 Exercise:

    W. Pauli(1900-1958)

  • Hunds Rule

    The German physicist Friedrich Hermann Hund established the rule wherein the lowest energy configuration is the one

    having the maximum number of unpaired electron of parallel spin in a particular set of degenerate orbitals.

    1. Write the electron configuration and box diagram for the following atoms:

    a) C

    b) N

    c) O

    d) F

    e) Ne

    2.13.2 Exercise:W. Hund

    (1896-1997)

  • Shorthand Notation

    Shows in brackets the noble gas element that most nearly precedes the element being considered:

    Mg (Z= 12): 1s22s22p63s2 or [Ne]3s2

    1. Write the shorthand notation for the following atoms:

    a) Na

    b) Al

    c) Si

    d) S

    e) Ar

    2.13.3 Exercises:

  • 2. Write the electron configuration and orbital box diagram for the following atoms:

    a) Sc

    b) Ti

    c) V

    3. Write the electron configuration for the following atoms:

    a) Mn

    b) Fe

    c) Co

    d) Ni

    e) Zn

    f) Pb

    g) Bi

    2.13.3 Exercises:

  • Exceptions:

    There is a greater stability with a completely half-filled d subshellor a completely filled d subshell.

    To accomplish this, electrons can be taken from the previous s orbitalto add to the d orbital.

    Ex. Cr: 1s2 2s2 2p6 3s2 3p6 4s1 3d5

    2p6

    1s2

    2s2

    3s2

    3p6

    3d5

    Cu: 1s2 2s2 2p6 3s2 3p6 4s1 3d10

    4s1

    2p6

    1s2

    2s2

    3s2

    3p6

    3d10

    4s1

  • Valence ElectronsA group:

    B group:

    The valence electrons are those in the highest n(will be the ones removes when a cation is formed).

    The valence electrons are those in the highest n & those in the (n 1) d orbital(those in the highest n will be removed first when forming a cation).

    Write the electron configuration for the following ions:

    a) Na+

    b) O2-

    c) Ti2+

    2.13.4 Exercise:

  • 2.15 Diamagnetism & Paramagnetism

    Paramagnetic substances: contain unpaired electrons in orbitals(these substances are attracted to a magnet).

    Diamagnetic substances: all electrons are paired(these substances are weakly repelled by a magnet).

    1. Write the electron configuration of the following atoms and determine if they are diamagnetic or paramagnetic:

    a) O

    b) Mg

    c) N

    d) Ar

    e) Zn

    f) Ti

    2.15.1 Exercise:

  • 2.16 The Periodic Table

    By 1869, a total of 63 elements had been discovered, and scientists were studying their physico-chemical properties.

    The chemist John Newlands classified these in order of increasing atomic mass and noticed that their

    properties repeated every 8 elements.

    J. Newlands (1837-1898)

    Newlands proposed the Law of octaves at the Chemical Society in London, but was ridiculized because of the parellel he did with the musical octave.

    Contact: This isnt noise, this has structure!

  • 2.16 The Periodic Table

    Drawing on Newlands discoveries, the Russian chemist Mendeleev grouped in familiesall elements with similar properties & created the 1st Periodic Table of Elements.

    D. Mendeleev (1834-1907)

    One advantages of his periodic table is that it classifies

    elements both vertically(groups or families) and

    horizontally (periods or rows).

    Because of the limited knowledge, Mendeleev left gaps in the periodic table of elements and correctly predicted the mass

    and chemical properties of the yet unkown elements.

  • Groups or families (vertical)

    Periods or rows (horizontal)

    Mass Number (A)

    Relative Atomic Mass

    The blue-print of all matter!

    1A

    2A

    3B

    8A

    3A 7A6A5A4A

    4B 5B 6B 7B 8B 1B 2B

    2.16 The Periodic Table

    A Group (Main Group): the representative elements (1A - 8A).

    B group: the transition metals (1B-8B).

    Inner transition metals: the 2 bottom rows (lanthanides & actinides).

  • 2.16 The Periodic Table

    Metals:

    Metalloids:

    Non-metals:

  • Alkali metals

    Alkali earth metals

    Transition metals Noble gases

    Halogens

    Non metals

    Other metals Lanthanides

    Semi metals Actinides

    2.16 The Periodic Table1A2A

    3B

    8A

    3A 7A6A5A4A

    4B 5B 6B 7B 8B 1B 2B

  • 2.17 End of Unit Exercises:1. The electron configuration of a neutral atom in its ground state is [Xe]6s24f145d6.

    a) What is the name and the symbol of the element?

    b) How many unpaired electrons does the above element have?

    c) Is the above element para or diamagnetic?

    d) Is the above a metal or a non-metal?

    2. For As (Z=33):

    a) Write a complete set of quantum numbers for each of the valence electrons.n m ms

    b) Complete a similar table for the valence electrons of Fe (Z=26),

    c) Complete a similar table for the valence electrons of Cl (Z=17),

    d) Complete a similar table for the valence electrons of Cr (Z=24),

    e) Complete a similar table for all electrons of N (Z=7).

  • 3. Give the full electron configuration and box diagram for each of the following species:

    a) Mo (Z=42)

    b) Cu (Z=29)

    c) Zr (Z=40)

    d) I-1 (Z=53)

    e) Au (Z=79)

    f) Zn2+ (Z=30)

    g) Fe2+ (Z=26)

    h) P-1 (Z=15)

    i) (Z=81)

    j) Fe3+ (Z=26)

    k) Po2- (Z=84)

    l) Cr (Z=24)

    4. Determine if the species in 3) are paramagnetic or diamagnetic.

    End of unit exercises:

  • 5. Write the name and the symbol of one element which is a/an:

    a) Halogen in the 5th period,

    b) First row transition metal,

    c) Alkaline earth metal in the 2nd period,

    d) Noble gas in the 3rd period,

    e) Member of the 4a family,

    f) Representative element of the 6th family,

    g) Alkali metal in the 6th period,

    h) Lanthanid,

    i) Actinide,

    j) Halogen with 74 neutrons.

    6. Give the name & symbol of the element which corresponds to each of the following information:

    a) The heaviest halogen without d electrons,b) The first element with five half-occupied 3d orbitals,c) The first element to have a d electron,d) The first element to have a p electron,e) The first element to have an f electron.

    End of unit exercises: