Transition Metals Chemistry: Properties, Oxidation States, and Complex Formation, Study notes of Chemistry

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13. Periodicity (HL)

Topic

13 : Elements with^ complete d-orbital are not considered (^) transition metals (^) , but (^) post-TM In block^ F: Cr and^ Cu: Er :^ Is: 23"Cp 35' (^) 3p45'3dX +s!^ "dE half-filled 29C :^ Is (^2) Is"

2ps 35

: 3ps as IUPAC elements (^) (post-transition) It BSIJBIS #"post- ↑ tran conthenoids actinoids fe

: (Ar]

45 3 da , CAr] It^ 12. Orbital (^) diagram when (^) removing e-from atom^ to^ make^ an^ lon^ , remove^ from valence shell Is^23 do

Fualence ex:^ remove ze-

4503d

lonic compound

+H

=hydrated salt

CuSO +. 5H,D^

He molecules hydrated salt feSO9.^ TH2O^ H2O has^ H-bond CaCI2. 2H cultSo,

(^50 50) forms H-bond^ with H

• • H (^) It from H bonds with

wit

col

Hed

OHe PO ↑ 3 (^2) atoms (^) of 2 diff (^5) H molecules

to pic ( Transition (^) metals are elements^ with (^) incomplete d-orbital. isfe Is"^25 Ips35^ 3 pSts3ds soIn Is"Is"^ 2pS^ 35"^ 3ps &s 3d"^ (not^ transitional belongs to blocka^ metal) but still (^) belongs to^ blocka

do

Block d

Y / and posttrance a

trans metal post-trans metal

Block &

It -^ periods ginner transitionmta used (^) for (^) everyday use:^ ex : Uranium Blocks (^) in (^) periodic table^ :

gr

(^1) alkali metals (except H) go

alkali eath metal

gr13-18 gr^ (^1) halogens E

go

18 noble (^) gases gr

3-11 transition^ metals

gr 12 post-transition metals

As blocks^

:

s-block :

grl ,^ go

2 , He

p-block :^ gr 12-18 (^) (exception He d-block : gr3- f-block :^ Lanthanides^ If^ (1^ element^ Lantinium^ , (a) E (^) actinides If (^) (itelement Actinium , Ac)

characteristics (^) of transition element: across (^) a (^) period (left-right

nuclear

charge (2)^

I

atomic (^) radius! It ↑

If I gradually lower^

in (^) main groups e-enter in^ an inner-shell orbital - transition^ greate (^) shielding effect e-enter in^ valence^ shell^ or^ orbital^ --main group ↑

Transition metal: · lons^ are^ often^

colored

·^ can^ form^ complexes^ with^ ligands · are^ often^ catalysts · have^ variable^ o^ .s^ (due^ to^ pattern in^ successive^ IEs) · (^) magnetic properties (paramagnetic diamagnetic)^ due^ to Ordinate single e-^ paired^ e- nb Transition metals^ have^ varying oxidation (^) states. Type

A

Type B Type C high-stable (^) high-stable high-unstable

low-unstable low-stable low-stable

Sc (^) , Ti^ , V^ Mn , Cr^ Feat iMn : (^) [Ar] 95 365 Must :^950 365 loses^ from^ 952 MnTt :^99036 ° loses (^) from 452 and 3 d 0.^ > (^) ranges from +^2 to^ + 7. Breathalyzer Test (^) : KzCr (^) ,On potassium dichromate yellow/orange-safe green

below-under max limit

green beyond^ (dark) - above max limit (^) (do not drive (^2) Cr07" + 3CH30^ +^ 16Ht2Cr*

• 3Cr^ ,

yellow -^ no^ alcohol

green

• (^) some alcohol heavy green

• (^) too much alcohol

polydental : (^) EDTA (^) (ethylendiamine retracetate) -CHe+-- CH-

N -^ N -C-CH (H) - C

all donors

6 coordinate^ bonds

Properties of^ EDTA: · has^ the^ ability to (^) wrap itself around^ the (^) transition metal^ center ·^ Can^ remove^ heavy metal^ (Pb') · used^ for Chelation^ therapy (hardening the^ arteries

. water^ softening (remove^ Ca't)^ shampoo · foot^ preservation (^) (rancidity) · restorative^ sculpture

. cosmetics

Coordinale number: Coctahedral ↑ coordinate^ nbr-tetrahedral^ 109 :^5 : Colle- & (^) square planar geometry : go (180) (^) Ni(CN) (^) , " 6 coordinate br:^ ochtahedral (FeCH (^) ,O)^ ,]^ " H20 (^) H20 USPER^ not^ applied (no e^ pairs ABs..^ ) -- & 6 => (^) X-ray crystallization -HO H,^0

Transition metals^ are^ used^ as catalysts :

Haber (^) process : (^) Fe(s) Decomposition of (^) H202 : (^) MnOz) Hydrogenation of^ alkene:^ Nick)-pdc)^

• Pt(s) oxidation Hydrogenation of^ oils^ : (^) Nick ist chamber: 20 ->^ W Catalytic converter (^) in cars : Pt()-cu und chamber^ :^ No (^) , N^ =^0 ,^ Noz^ N Biologic Catalyst : Hemoglobin (fe) Type of (^) Catalyst : · Homogenous:^ reactants^ and^ catalyst^ same^ phase . (^) Heterogenous :^ reactants^ and^ catalyst diff (^) phase usually ex:^ Haber (^) process N2) +^ 3 H^ , E2NHaca)^ neterogenous B. 2.^ Colored^ Complexes: Transition metals^ have^ incomplete d-orbital di ,de,^ da^ da,^ di split adde ↑ Do

1 t2g

d'd'd Crystal Field^ Theory :

didade de-di

CfT electrostatic^ model

ligands are considered^ as point changes that^ surround^ the^ metal^

cation

un

un

ligh To

lig

Octahedral

example:^

d-orbitals

split

into two set

• teg are^ stabilized^ , 45 : (lower (^) energy
• eg ,^ destabilized^ ,^ higher energy^ 3 Do (^) : (^) crystal field (^) splitting (^) energy

3 Nature of (^) Ligand : 5 .<Br^ (Cl<F-CrOt=^ H2O^ <^ NHsCethanamin(phen^ <NO (^) , (N

= CO

y3tweak (^) Ligand

M

weak weak:^ fills (^) tegthen eg(Hund's (^) rule) 11 1101. strong:^ fills^ teg^ with (^) paired e- 111111

• Geometry of^ the complex ion : color shows^ means its^ complimentary

colors absort

zaw--purple

summary: · (^) d-block elements^ are^ elements^ in^ d-bokk^ with^ onincomplete sub level. Sc - >^ m^ -^ In ↑ (^) not trans element but^ is^ n

block d.

and (^) finla : ↑ CAr] 45'3d

fe :^ [Ar] Is 3ds^10 d-block

mu but 9 trans^ metals

Se in incomple

↓ Y CAr]^ Is^ 3d felt Fest (^) 4523d [Ar]4503d5 (^) , 3d

[Ar] +503d^ or

or 3ds 365

• ... .^ remove^ from

alter ashell^ first

(4tn 3)

~^ ~y prop chemical^ prop^ half-filled · (^) high elec.^ ·^ more^ than^ one^ oxidation^ : Lars use

and Hermal^ state in componds 29

conductivity (^) pr:^ [Ar]^ ... · (^) high (^) melting points^

ofor^ complex^ ,one

· magnetic

I

· act^ as^ catalysts

exception:

• malleable a^ ductive^ a (^) form colored ump in^ solution

· high ensilestrengt

properties

• (^) - · electric^ und · more than^ I^ oxi stated t : · (^) malleable & (^) ductive · nigh MP · implex in · colved^

comp

in solo · (^) magnetic (^) prop ·catalystsM^ :

Topic 13 : d-block elements^ are^ elements^ in^ d-block^ withon incomplete +orbital transition metals (^) are in^ -block^ (exceptions like^ 2n^ , etc) complexions consist^ of a^ central^ metal^ ion^ bonded^ to^ ligands by

coordinate covalent bonds.

central example :

• metal ion L I -H

Cu

• H cuCH20o]" Togance ligands are Properties (^) of transition^ metals^ : physical Chemical · incomplete J-orbitals^ · (^) high electrical^ conductivity ·malleable^

& ductile

· Variable^ oxidation states

· magnetic properties^. act (^) as catalysts · high MP^ &BP (tue to metallic (^) bonding · (^) form complex ions Oxidation states: Cr't (^) , Cust (^) Type A^ Type B^ Type C Felt (^) , fest (^) high-stable (^) high-stable high-unstable

cut

, cu' low-instable^ low-stable^ low-stable

·Oxidation^ states^ : ·^ Chromium^

(II) crat

• 2

Crit , Cust

1/ (I)^23

• (^) + 3 Felt (^) , fest · loon^

cron(I) felt

iron (11)^

fest +y^ cut^

,

cut

Co't , Co2t

McKel (1) Nict

• 2

• c + (^) + 1 · (^) copper (^) mi+^ +^2

• (^2)

·^ Cobalt^

Cor

, cost^ +

If (^) ligands are^ neutral (^) , the (^) charge on^ the^ central metal^ ion^ =^ comple : & 101 NH HNs cu-NHa 2 + S I HNY 1 NHL^7 Se... Nitz (C^ (NHz)o]2t q

charge of^ antial^

metal (in^ (m) = charge of^ complexion =^ +^2 10.^ 3)

·^ transition^ element^ have^ variable^ oxidation^ state

type A type B type ( [Co(NH3) , ]C high-stable high-stable^ high-unstable (^) T so^

• 3c

low-unstable low-stable^ low-stable ask

ex : Mn2 ,^ Mn^

• (^2) Determing charge^ in^ complex con (^) : Eneutrali Fanegativelycharged^ : You just

add

[Cu(NHs) (^) ,]'t^ charge of (^) complex on^

• total (^) charge
• 1. S^ NHy^ =^0 ex :^ (Co (NHz)^ ,^ Cle] of (^) ligands
• o.^ S ion^ =^ +^2 i I rig

=

0. m =^ +^2 P^

x (^) + 6207 --^ +^2 HM ,

Co

Why neutral^ 2Cl = 2 / (^) = (^) j x =^ +^2 HNey (^) , Nots

• -^1

• 2. = + 3 =^ (

· color^ wheel^ :

colored (^) compounds : KMnOd (MnCH2O)s]"^ (CrCH2O)s] 3

KiCr2O CuSO

purple colorless green yellow-^ blue

orange

As wavelength increases^ , absorbance^ ↑

100950500500 ...^700

Colored

Complexes : Properties of^ complex^ ions (^) are caused by splitting^ of^ d-orbital into (^2) sets (^) of (^) diff. energies (^). 2 higher dry ae · Splitting occurs^ as a result (^) of when (^) ligands approach central metal ion (^) , causing repulsion^ blu^ love (^) pairs (^) of- on ligands and (^) e-in the^5 d-orbitals (^) ofeutral (^) metal (^) ion. ·^ e-transition^ from (^) lower-higher set^ of^ borbital Cabsorption) transmitted absorbed crystal field thing : splitting ofd-orbitals into^2 sets^ of^ energie

~paramagnet

a I

diamagnetic

• (^) (paired et

(^0) : (^) 11. choice depends on^ the type of (^) ligand. ⑦ ! (^) strong ligand

would

go for

111111 need^ energy for

weak ligand would go for

pairing