CHE2C Transition Metals

Radii pattern on Periodic Table

Decrease then increase across a row (nuclear charge draws d e- inwards = decreasing radius. As d e- increase, e- e- repulsion increases —> increasing radius)

2nd & 3rd row nearly the same (lanthanide contraction, f e- of lanthanides don’t shielf nucleus well, causing contraction

Density pattern on Periodic Table

Increases then decreases (inversely proportional to volume)
3rd row significantly higher densities bc lanthanide contraction (less volume) & higher mass

Where are higher oxidation states more stable?

2nd and 3rd row

What is the common transition metal oxidation state and where are the e- lost?

+2, loss of both s-e-

Which columns of Transition Metals don’t fill as expected? How do they fill?

e- in the 4th (Cr) and 9th (9th) column. Only 1 e- fills the s-orbital

Where are e- removed first for transition metals? (orbitals)

s e- are removed before d e-

Do Transition metals have ionic or covalent character?

both

Which transition metals have color?

any metal with partially filled d-subshells

Which transition metals are colorless or white?

filled and unfilled subshells

What is ferromagnetic?

permanent domains of magnetism

Why are TM great catalysts?

1. Multiple ox states and coordination numbers possible

2. ligands can easily bond and multiple bonding sites available

   1. generally coordinatively unsaturated (can accept more ligands)

What kinds of reactions do TM undergo?

1. Combination

2. Decomposition

3. Single Replacement

   1. Double Replacement

What is Metallurgy?

the process of refining metal ore to the pure metal for industrial use and applications

Scandium

ox state: +3 most common

act similar to AL, Y, and lanthanides bc cation has no d e-

diamagnetic so colorless

Titanium

low density, high strength, low corrosion

similar properties to C and Si

ox state: +3, +4

Vanadium

makes strong and tough steels

compounds are toxic

ox state: +5 most common, +2 through +5 exist

Chromium

corrosion resistant

many compounds have intense colors

toxic and carcinogenic

ox states: +2, +3, +6

Manganese

ox state: +2, +7

applications:batteries, catalyst (MnO2)

Iron Family

most common element by mass on Earth, forms inner and outer core

form metal carbonyl bonds (M - CO)

ox states: +2,+3

Cobalt Family

ferromagnetic

used to color glass, changes color a lot

form metal carbonyl bonds (M - CO)

easily takes ligands

ox states: +2, +3

Nickel Family

corrosion-resistant

“double-magic” = extremely stable

form metal carbonyl bonds (M - CO)

ox state: +2

Copper Family (Coinage Metals)

bronze and crass alloy

durability and corrosion-resistant

naturally blue

high conductivity

ox states: +1, +2

Zinc Family

ox state: +2

corrosion-resistant, hard, brittle, diamagnetic, reducing agent

common sacrificial anode

Lanthanides

f e- don’t play a big role in bonding, elements in series have similar chemistry to each other

similar to Sc and Y

highly reactive with halogens and chalcogens

ox state: +3 common, +2, +4

low toxicity

Actinides

all radioactive and paramagnetic

similar properties to lanthanides

toxic due to radioactivity

Linear

Trigonal planar

Bent (Trigonal planar)

Tetrahedral

Trigonal pyramidal (tetrahedral)

Bent (tetrahedral)

Trigonal Bipyramidal

Seesaw (Trigonal Bipyramidal)

T-shaped (Trigonal Bipyramidal)

Linear (Trigonal Bipyramidal)

Octahedral

Square pyramidal (Octahedral)

Square planar (octahedral)

Coordination Compound

TM ions, in combination with ligands and counter ions, form these compounds.

General term for neutral compounds that contain TMs

Complex Ions

TM ions in combination with ligands form these compounds

This term is used when the TM species has a nonzero charge

Counter Ions

Anions or cations needed to produce a compound with no net charge

appropriate counter ions added to a complex ion (charged) to make it a coordination compound (neutral)

Ligands

Groups (not including counter ions) that surround the transition metal ions

Coordination Number (CN)

Number of nearest neighbors to the transition metal ion (usually ligands)

count the number of ligands around the TM ion, can vary from 2 to 12

Complex

general term for any species involving ligands connected to a transition metal ion

Ox State

Primary valence of the TM

Ligands will have

1. lone pair or e- ready to form a bond

   1. Neutral or negative charge

Monodentate

A ligand with one pair of e- to attach to the TM

Polydentate

A ligand with 2 or more pairs of e- to attach (bond) to the TM

H2O

Neutral, Aqua

NH3

Neutral, Ammine

CO

Neutral, Carbonyl

NO

Neutral, Nitrosyl

CH3NH2

Neutral, Methylamine

C5H5N

Neutral, Pyridine

F-

Anions, Fluoro

Cl-

Anion, Chloro

Br-

Anion Bromo

I-

Anion, Iodo

O²-

anion, oxo

OH-

anion, hydroxo

CN-

Anion, Cyano

SO4²-

Anion, Sulfato

S2O3²-

Anion, Thiosulfato

NO2-

Anion Nitrito-N-

ONO-

Anion Nitrito-O-

SCN-

Anion, Thiocyanato-S-

NCS-

Anion, Thiocyanato-N-

en

Bidentate

ox²- or C2O4²-

Bidentate

Nomenclature: When considering a complex ion and the counter ion, are cation named first or anions?

cation first

composite ligand

ligands that contain a prefix in its name (ex: en and EDTA^4-), must used composite prefixes

How does the naming of the complex ion work?

Ligands are named in alphabetical order first (not including prefix) and then the metal with ox state is named last

• complex ion is anion —> metal must be named in Latin if possible with suffix ate

• complex ion is cation, metal is named in English with no additional suffix

Composite Prefix for 2

Bis-

Composite Prefix for 3

Tris-

Composite Prefix for 4

Tetrakis-

Latin Name for Iron

Ferrate

Latin Name for Copper

Cuprate

Latin Name for Tin

Stannate

Latin Name for Silver

Argentate

Latin Name for Lead

Plumbate

Latin Name for Gold

Aurate

IS the TM cationic or anionic?

cationic

How to tell if the complex is positive or negative?

[ ] listed first = cationic

[ ] listed second = anionic

Ionization Isomers

A structural isomer where a ligand and a counter ion switch

coordination isomers

a structural isomer where the transition metals of a bi-metallic (2 metal) species switch ligands

linkage isomers:

A structural isomer where a multi-atom ligand connects to the TM through different atoms

Geometric Isomers:

A stereoisomer where the arrangement of the ligands are either neighboring (cis or fac) or across (trans or mer) from each other

trans

2 identical ligands are bonded across from each other (2ligands same axis)

VSEPR shape: Square Planar or Octahedral

Chiral not possible

cis

2 identical ligands are bonded neighboring each other (2 ligands different axis)

VSEPR shape: square planar or octahedral

chiral possible

fac

3 identical ligands are bonded neighboring each other (3 different axes)

VSEPR shape: Octahedral

chiral possible

mer

3 identical ligands, and 2 of the 3 are bonded on the same axis

VSEPR shape: Octahedral

no chiral

optical isomer/chiral

mirror image is different

When can a tetrahedral be a optical isomer?

Only is all 4 ligands are different

When can a octahedral be a optical isomer?

all 6 ligands are different

etc.

can a complex be both a geometric and an optical isomer at the same time?

yes

Is attraction low energy or high energy? What about repulsion?

attraction is low E, repulsion is high E

Octahedral CFT

each L is attempting to bond with M on the axis, so dx²-y²and dz² exist at high E

Tetrahedral CFT

each L is attempting to bond with M off the axis, so dx²-y² and dx² are low E

Square Planar CFT

Ligands are on the xy axes

Linear Shape CFT

highest E is the dz² orbital bc it lies right on the z axis