Test 3

Front 1

what is a complex ion?

Back 1

A metal ion and a lewis base/bases bonded to it.

Front 2

What is Kf

Back 2

the formation constant. the constant for a complex ion.

Front 3

If Kf is large we assume that

Back 3

the transition metal of a complex ion has all converted to the complex ion and approach the problem as a dissociation not a formation. therefore the complex ion will take on the molarity or conc of the inital conc of the metal ion.

Front 4

complex ions ____ the conc of the free transition metal ion

Back 4

reduces in solution.

Front 5

the solubility of metal salts ____ in the prescence of lewis bases if it forms a complex ion

Back 5

increases

Front 6

What are amphoteric hydroxides and amphoteric oxides

Back 6

are insoluble substances in water that dissolve in strong acid or strong base solutions because they act as either an acid or a base.

examples Al3+, Cr3+, Zn2+, and Sn2+.

Front 7

What are ligands

Back 7

molecules or ions that bond to the metal ion in a complex. lewis bases. it donates a pair of electrons to form the ligand-metal bond. most are either polar molecules or anions.

Front 8

What are common ligands

Back 8

water, ammonia, carbon monoxide, many organic bases, hydroxide, cyanide, and other anions.

Front 9

To be a lewis bases you have to have

Back 9

a lone pair of electrons to donate.

Front 10

polydentate

Back 10

A single ligand that can make more than one bond to a metal.

ex: ethylenediamine. (en)

Front 11

what is chelated

Back 11

a term used when metals are bonded to polydentate ligands. usually a very strong bond.

Front 12

bidente ligand

Back 12

makes two bonds

exs: carbonate and oxalate

Front 13

coordination number

Back 13

the number of ligand bonds to a metal.

Front 14

oxidation state

Back 14

primary valence

Front 15

coordination number

Back 15

the secondary valence; the number of atoms bonded to the metal ion.

Front 16

draw the diagram for ehtylenediamine

Back 16

...

Front 17

How do you name complex ions and coordination compounds

Back 17

...

Front 18

what are the metals that have an exact overall charge no matter what

Back 18

Ag+, Zn2+, and Al3+

Front 19

when the ligand name already contains a prefix or is a polydentate how do you name it;

example: ethylenediamine

Back 19

2-bis

3-tris

4-tetrakis

5-pentakis

Front 20

To write the formula given the name of the coordination compound

Back 20

1. we know that the words attached to eachother is the complex ion or the ones in brackets.

2. the outside is either a cation or an anion

3. the compound should be neutral meaning the charge is equal to zero.

4. we write the metal first, then the neutral ligand if there is one and then the anion.

5. if there more than one neutral ligand than you first figure out the chemical formula for each, then depending on that write the first one that is in alphabetical order. example; CO before NH3.

Front 21

Name of Metals in Anionic Complexes

Back 21

Iron

Ferrate

Copper

Cuprate

Lead

Plumbate

Silver

Argenate

Gold

Aurate

Tin

Stannate

Front 22

shape of a complex ion depends on the

Back 22

coordination number

Front 23

c.n. for linear shape of complex ion

Back 23

c.n. 2

Front 24

c.n. for trigonal planar shape of complex ion

Back 24

c.n. 3

Front 25

c.n. for tetrahedral or square planar shape of complex ion

Back 25

c.n. 4

Front 26

c.n. for trigonal bipyramid shape of complex ion

Back 26

c.n. 5

Front 27

c.n. for octahedral shape of complex ion

Back 27

c.n. 6

Front 28

most common coordination numbers

Back 28

2,4, and 6.

Front 29

the coordination number depends on

Back 29

what is the metal cation?

what is the charge on the metal?

how big is the ligand? and more.

Front 30

usually the c.n. is

Back 30

two times the charge of the metal if you don't have the formula given.

Front 31

isomers

Back 31

two different compounds w/ the same molecular formula. so they have different names.

example is C2H6O

Front 32

know how to draw ethanol and know its formula

Back 32

...

Front 33

know how to draw dimethyl ether and its formula

Back 33

...

Front 34

the color of a complex depends on

Back 34

the identity of the metal ion, the metal ion's oxidation state, and the ligands bound to it.

Front 35

to see color, the substance must

Back 35

absorb some portion of the spectrum of visible light. Absorption happens only if the energy needed to move an electron in the substance from its ground state to an excited state corresponds to the energy of some portion of the visible spectrum.

Front 36

the color we perceive is

Back 36

the sum of the unabsorbed portions which are either reflected or transmitted by the object and strikes our eyes.

Front 37

opaque objects

Back 37

reflect light

Front 38

transparent objects

Back 38

transmit light

Front 39

an object appears black if

Back 39

it absorbs all wavelengths of visible light.

Front 40

an object is colorless liquid or white solid if

Back 40

the object absorbs no visible light

Front 41

we see the color orange if

Back 41

the object absorbs all but orange light or when an object absorbs only the blue portion of the visible spectrum and all the other colors strike our eyes. blue is the complimentary color of orange.

Front 42

draw the color wheel and the wavelengths that go with it.

Back 42

...

Front 43

Crystal Field Theory

Back 43

Helps explain and predict the colors and magnetic properties of complex ions.

This model looks at the interactions between the d-orbitals and the ligand electrons.

The ligands are negative points of charge that repel the electrons in the d orbitals of the metal ion.

Front 44

octahedral crystal field

Back 44

For an octahedral shape of a metal ion there are six ligands that surround the metal ion but approach it at different directions on the x y and z axes. because of this they don't have the same repulsion from the ligands and therefore the d orbitals don't all have the same energy.

only 5 orbitals.

Front 45

know how to draw all orbitals of the octahedral crystal field

Back 45

...

Front 46

what is true about the dz2 and dx2-dy2 orbitals

Back 46

that the orbitals are directed along the x, y, and z axes and point directly toward the ligand point charges. they have a higher energy than the other orbitals but they both have the same amount of energy. this is because electrons in the metal ions orbitals experience stronger repulsions thus causing an energy splitting or gap of energy between these orbitals and the other 3 orbitals.

this is called the 3 set

Front 47

what is true about the dxy dxz and dyz orbitals

Back 47

that these orbitals lie in between the axes and don't point directly toward the ligand charges

they have a lower amount of energy than the other orbitals. have weaker electron repulsions. this is called the t2 set.

Front 48

crystal-field splitting energy

Back 48

energy gap (delta) between the two sets; e set has a higher energy than t2 set.

Front 49

know how to draw the free metal ion and the octahedral crystal field diagram pg. 988

Back 49

...

Front 50

due to the energy gap of the octahedral crystal field, a transition metal complex is able to absorb visible light that excites an electron from a lower energy (t2) d orbital to a higher energy (e) orbital.

Back 50

this is called a d-d transition.

Front 51

what is the spectrochemical series

Back 51

a ranking which ligands are arranged in order of their abilities to increase splitting energy. shows how much splitting each ligand causes. the magnitude of delta increases by about a factor of 2. at the low end are weak-field ligands and at the high end are strong-field ligands.

Front 52

The greater the crystal-field strength of the ligangd, the

Back 52

greater the energy gap delta it causes between the t2 set and the e set of d orbitals.

Front 53

know how to write the spectrochemical series

Back 53

I

Front 54

to calculate the crystal field splitting use this formula

Back 54

E=hc/wavelength

h=Planck's constant=6.63 times 10 to the -34 J * sec

c=speed of light=3.0 times 10 to the 8th m/sec

if you stick to meters, kelvin, secs energy comes out as Joules.

we also know that there is ____joules for every 1 photon of energy.

for every 1 mole there is 6.02 times 10 to the -23 photons.

answer should be in J/mole or kJ/mole.

Front 55

3 major types of magnetic properties

Back 55

ferromagnetism; permanent magnet

paramagnetism; has at least 1 unpaired electron

diamagnetic; has zero net electron spin so all electrons are paired.

Front 56

spin-pairing energy

Back 56

the difference between the energy required to pair an electron in an occupied orbital and the energy required to place that electron in an empty orbital.

It also says that electrostatic repulsion between two electrons that share an orbital (has opp. spins) is greater than the repulsion between two electrons that are in different orbitals and have parallel spins.

Front 57

high-spin complex

Back 57

electrons are unpaired as much as possible

congruent with small energy

Front 58

low-spin complex

Back 58

electrons remain paired as much as possible while following Hund's rule of filling at the lower energy orbitals first.

congruent with large energy

Front 59

two main types of isomers

Back 59

structural isomers; have different bonds

stereoisomers; have the same bonds but different ways in which the ligands occupy the space around the metal center

Front 60

types of structural isomers

Back 60

coordination-sphere isomers (ionzation isomers) and linkage isomers

Front 61

types of stereoisomers

Back 61

geometric isomers and optical isomers

Front 62

linkage isomerism

Back 62

happens when a ligand is coordinating to a metal in two ways usually through either its nitrogen or its oxygen atom.

Front 63

example of a linkage isomer and draw

Back 63

OCN-

Front 64

coordination-sphere isomers

Back 64

they differ in which species in the complex are ligands and which are outside the coordination sphere.

Front 65

example of a coordination-sphere isomer and draw diagram

Back 65

Cr(NH3)4Cl2Br

Front 66

geometric isomerism

Back 66

arrangement of atoms is different but the same bonds are present

deals with cis and trans.

cis isomer=ligands in adjacent positions, on the same side

trans isomer=ligands are on opposite sides of the central atom.

have different physical properties and different chemical reactivities.

possible in octahedral complexes when two or more different ligands are present.

Front 67

example of geometric isomer and draw diagram

Back 67

[Pt(NH3)2Cl2]

Front 68

optical isomerism

Back 68

also called enantiomers; are mirror images. we can't twist and turn our right hand to make it look identical to our left. there is no way to make the isomer identical to the other.

this can happen in tetrahedral structures with 4 different groups attached or when you have an octahedral complex with 3 bidentate ligands.

Front 69

example of an optical isomer and draw diagram

Back 69

[ZnClBrNH3OH]- or [Cr(en)3]3+

Front 70

How do enantiomers differ

Back 70

1. the two enantiomers rotate plane-polarized light in opposite directions.

2. they differ in chemical reactions with other molecules that have enantiomers.

Front 71

an excess of either NH3 or NaOH

Back 71

can but no always produce a complex ion but only a small amount of base cannot.