L2 - Properties of the Elements -1 PDF

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Meet$the$Elements! • http://www.youtube.com/watch?v=Uy0m7jnyv6U They;Might;Be;Giants,;Here;Comes;Science;(2009)

EOSC$333:$Geochemistry • Week;1;; • Week;2; • Week;3; • Week;4; • Week;5;

• Week;6; • Week;7;

Introductory;activity:;the;Periodic;Table;;Course;overview Properties$of$the$Elements$#1$and;#2 Analytical;Methods;in;Geochemistry;#1:;XRF,;ICP-MS Major;Element;Geochemistry Geochemical;Behaviour of;Trace;Elements Toolkit Partition;Coefficients,;Melting/Crystallization Analytical;Methods;in;Geochemistry;#2:;In-situ;Techniques; (microprobe,;laser;ablation,;SIMS) Mass;spectrometry;&;Analyzing;Geochemical;Data Radioactivity Isochron Principles;&;Isotope;Systems;(Rb-Sr,;Sm-Nd,;Lu-Hf) No#class#on#Feb#13,#Family#Day Feb$15$Mid-Term$Exam

• Week;8

Mid-Term$Break$- reading$week

• Week;9

Geochemistry;of;Magmas;&;Differentiation;#1;and;;#2 Forward;geochemical;modeling;with;PELE/MELTS

Properties$of$the$Elements: Lecture$outcomes ü Review;of;nuclear;physics;and;basic;chemistry;principles ü Recognize#that#the#periodic#table#is#fun#and#has#many#hidden#secrets ü Define;charge,;size,;electronegativity;and;describe;their;role;in; element;partitioning ü Long-term$goals:;describe;how;different;groups;of;elements;behave; in;different;geological;and;environmental;materials;and;settings. Reading$material:$Albarède,$Chapter$1. W.M$White's$book$Ch.$1,$p.$1-6.

Physics'of'the'Nucleus Some$definitions N:$number$of$neutrons Z:$number$of$protons =;atomic;number;since;the;number;of;protons;dictates;the;chemical;properties;of;the; atom.

A$=$Z+N,$Mass$number$- Different$from$M:$Atomic$Mass

Notation:

A

X$$or ZXN$$$nuclear;species;or;nuclide

Isotopes:$same$Z,$different$N Isobars:$same$mass$number Isotones:$same$N,$different$Z

Image;from;http://www.siyavula.com/

Chart'of'the'Nuclides:'AX''or ZXN'

Isotones

Z

Isotopes 12C;;13C;;14C The distribution of elements moves away from the 1:1 line. The more protons there are in the nucleus, the more neutrons you need to compensate for the electrical propulsion.! ! The black dots are the distribution of the stable configuration.

87Rb;;87Sr

N

Physics'of'the'Nucleus Some$definitions N:$number$of$neutrons Z:$number$of$protons =;atomic;number;since;the;number;of;protons;dictates;the;chemical;properties;of;the; atom.

A$=$Z+N,$Mass$number$- Different$from$M:$Atomic$Mass

Notation:

A

X$$or ZXN$$$nuclear;species;or;nuclide

Isotopes:$same$Z,$different$N Isobars:$same$mass$number Isotones:$same$N,$different$Z Stable$isotope:$an$isotope$that$is$time$invariant Radioactive$isotope:$an$isotope$that$decays$with$time Radiogenic$isotope:$an$isotope$that$is$produced$(at$least$in$part)$by$decay$from$a$ radioactive$isotope.

Chart'of'the'Nuclides:'Overview Grey area - configurations that are possible but not stable

Large$A:$N>Z

Small$A:$Z=N Observations:

Albarède#Fig.#1.1

ü Not;all;elements;are;stable;(limit;a;Z=92,;U). ü Stable;elements;have;approximately;the;same;number;of;protons;and;number;of;neutrons;(central; path;of;stability):;this;relationship;defines;the;valley$of$stability. ü Radioactive;isotopes;with;longer;half;lives;(and;still;present;in;the;solar;system);are;also;near;that; valley:;N$=$Z$+$Z2/160. ü Elements;that;deviate;significantly;from;this;rule;are;unstable$(radioactive). ü Instability;of;the;nuclides;increases;away;from;the;central;path.

Source:;Sam;Kean,;The;Disappearing;Spoon:;And;Other;True;Tales;of;Madness,;Love,;and;the;History;of;the; World;from;the;Periodic;Table;of;the;Elements.;Back;Bay;Books,;2011.

Source:;Sam;Kean,;The;Disappearing;Spoon:;And;Other;True;Tales;of;Madness,;Love,;and;the;History;of;the; World;from;the;Periodic;Table;of;the;Elements.;Back;Bay;Books,;2011.

Periodic'Table • A;very;useful;website;is: WebElements:$the$periodic$table$on$the$web http://www.webelements.com/ http://www.webelements.com/periodicity/abundance_crust/ • http://www.ptable.com/

• Theodore$Gray:$the$Elements http://www.youtube.com/watch?v=7FesjAdIWBk http://periodictable.com/index.html The;book: http://periodictable.com/theelements/index.html Nd element http://periodictable.com/Elements/060/index.html

Periodic'Table

http://www.nist.gov/pml/data/periodic.cfm

http://periodictable.com/

Periods

The Periodic Table of the Elements, in Pictures Alkali Me Gro H

Noble Gases 18

The color of the symbol is

e

Hydr

2

Helium

1

1 Sun St Li

Balloons e

Lith

Neon

10

2

2 Advertising Signs

Batt Na

r

Sod

Argon

18

3

3 ight Bulbs

S K

2

Pota

Krypton

36

4

4 Fruit Veget Rb Rubi

Flashlights 4

e

ht s

gh-Intensity Lamps

Xenon

54

5

5 Glo Navig Cs

7

Ces

Radon

86

6

6 Ato Clo

gs

Surgical Implants

Fr Fran

0

118 g Oganesson

La Atom

iv

7

7

8

6 m

71 Lutetium

t

otodynamic Medicine 103 Lawrencium

6

Actinium

Thorium

Protactinium

Uranium

Neptunium

9 Plutonium

Americium

Curium

Berkelium

Californium

Radioactive Medicine

Gas Lamp Mantles

Radioactive Waste

Nuclear Power

Radioactive Waste

Nuclear Weapons

Smoke Detectors

Mineral Analyzers

Radioactive Waste

Mineral Analyzers

Einsteinium

Fermium

Mendelevium

Nobelium

Actinide Metals

7 radioactive, never found in nature, no uses except atomic research

© 2005–2016 Keith Enevoldsen elements.wlonk.com Creative Commons Attribution-ShareAlike 4.0 International License

Sheehan,#W.#F.#Chemistry#1978,49,#11.

Periodic$Table$Arrangements • Alternative;arrangements: – Wide-form – Spiral – 3D

©;Maverick149

Robert;W.;Harrison http://spiralperiodictable.com/

Theodor;Benfey;(1964)

18;columns

7;rows

Each;brick;=;1;element

2;rows

Element;=;Nucleus orbited;by;Electrons Source:;Sam;Kean,;The;Disappearing;Spoon:;And;Other;True;Tales;of;Madness,;Love,;and;the;History;of;the; World;from;the;Periodic;Table;of;the;Elements.;Back;Bay;Books,;2011.

Orbits'(or'orbitals) examples'of'geometry

• Electrons balance charge! • Determine characteristics of elements

probability$ distribution$of$an$ electron$around$ the$nucleus s,p,d,f are$the$ quantum$ numbers: characteristics$of$the$ spectroscopic$lines:$ sharp,$principal,$ diffuse$and$ fundamental,$the$rest$ being$named$in$ alphabetical$order.

http://www.orbitals.com/orb/orbtable.htm

Albarède#Fig.#1.3

Electronic'Configuration'of'the'Light'Elements

Albarède#Table#1.1

Quantum$numbers: 1$n$principal:$positive$values:$1,2,3,$… 2$l$azimuthal:$ranges$from$0$to$n-1$ 3$m$magnetic:$0,±1,$…,±l$ 4$s$spin:$values$of$-1/2$or$+1/2 Pauli$exclusion$principle$states$that$ no$two$electrons$can$have$the$same$ quantum$number.

§ n$defines$the$general$energy$level$of$the$electron$(i.e.$the$main$electron$shells$(K,$L,$M,$…)$ as$well$as$the$distance$to$the$nucleus). § l$determines$the$total$angular$momentum$and$the$shape$of$the$orbit$of$each$shell$ (usually$described$by$the$letters$s,$p,$d,$f). § m$determines$the$z$component$of$the$angular$momentum$and$therefore$the$orientation$ of$the$orbit.$It$describes$the$shape$in$presence$of$a$magnetic$field.

§ s$(or$ms)$describes$the$relative$direction$of$spin$of$the$electron$around$the$nucleus.

Orbitals$filling$&$distribution$in$the$periodic$table (note#the#different#organization#of#the#table)

http://www.ptable.com/

Watch: 1. The$distribution$of$colors,$s,$p,$d$and$f$within$the$periodic$table, 2. How$the$filling$of$orbitals$evolve$within$a$column$for$instance,$Ti,$ Zr,$Hf 3. How$the$orbitals$rotate,$and$the$quantum$numbers$vary 4. The$role$of$4f$for$the$REE,$from$La=57$to$Lu=71.

Electronic$Configuration$of$the$Elements

r

Only;the;last;orbitals;filled;are;shown,;thus;each;element;has;electrons;in;the;orbitals;of;all; previous;group;18;elements;(noble;gases);in;addition;to;those;shown.;;Superscripts;indicate;the; number;of;electrons;in;each;subshell. White#Geochem#Fig.#1.3

Some'Chemical'Properties

ü Only;the;most;loosely;bound;electrons;(outermost;shells);participate;in;chemical; bonding:;so,;elements$sharing$a$similar$outermost$electronic$configuration$tend$to$behave$ similarly (group;or;column)

§ Group;1:;the;alkalis;have;1;electron;in;the;s;orbital § Group;18:;the;noble,;or;rare,;gases;have;a;filled;p;subshell. ü Ionization$potential: § First;IP:;energy;required;to;remove;(i.e.;move;to;an;infinite;distance;away);the;least; tightly;bound;electron.;This;is;the;energy;absorbed;by;the;electron;in;reactions;such;as:; Na;;;;;;;Na+ +;e§ Second;IP:;energy;required;to;remove;a;second;electron.

ü Electron$affinity:$energy;given;up;in;such;reactions;such;as; F;+;e-

F-

ü Electronegativity:$relative,;unitless quantity that;measures;the;tendency;of;an;element to;attract;a;shared;electron;when;bonded to;another;element.

White#Geochem#Fig.#1.4

2500 He

25 P$2

Ne

P$3

Period$4

Period$5

Period$6

2000

20 F

1500

Ar

N H

Be

1000

O C

Cl P

Mg B 500

0

Li

Na

10

S

Zn Fe

Si Al

Co

Ca K

18

15

Kr Br As

Cd MoPd

Se Ge Ga

Sr Rb

36

I

Xe

Rn

Te

Os

10

Sb Sn In Ba Nd Cs

Po Hf Pb Bi Tl Ra

5

54

86

Atomic$Number$Z

Ionization$energy$(eV)

Ionization$energy$(kJ/mole)

Ionization'Energy'vs'Z

Electronegativities

First$ionization$potential Electron$affinity$and Electronegativity

F,#4.0#:#electronegativity#>>#H,#2.1:#the#bonding#electron#in#hydrogen#fluoride,# HF,#is#more#likely#to#be#found#in#the#vicinity#of#F#than#of#H.#It#is#also#useful#in# characterizing#the#nature#of#the#chemical#bonds#between#elements.

Electronegativities;of;the;elements.;As;a;general;rule,;electronegativities;decrease;from;top;to;bottom;in;a; group;and;increase;from;left;to;right;in;a;period;of;elements. The;values;are;from;L.;Pauling,;The;Nature;of;the;Chemical;Bond,;3rd;edition,;Cornell;University,;Ithaca,;NY,;1960,;p.;93. They;may;be;somewhat;different;from;values;based;on;other;scales.

Valence:$number$of$electrons$that$an$element$will$either$give$up$or$accept. General;Chemistry:;Principles;and;Modern;Applications:;Petrucci et;al.

Ionic'Radius

The;ionic;radius;is;deduced;from;bond;length;when;the;atom;is;bonded;to;one;or;more;other; atoms.;Positively;charged;atoms,;cations,;have;smaller;ionic;radii;than;do;negatively;charged; atoms,;anions. Ionic;radius;also;decreases;as;charge;increases;because;of;the;loss;of;electrons;and;the; shrinking;of;the;orbits;of;the;remaining;electrons.

Ionic$radius$is$important$in$determining$important$geochemical$properties$ such$as$substitution$in$solids,$solubility,$and$diffusion$rates. Ionic;radius;increases;downward;in;each;group;in;the;periodic;table;(addition;of;electrons;to; outer;shells;and;increased;shielding;from;the;nucleus).; White#Geochem#Fig.#1.6

Atomic$Radii$of$the$d-block$Elements Lu

Atkins,#P.#W.,#Jones,#L.#L.#Chemistry:#Molecules,#Matter,# and#Change,#3rd#ed.#W.#H.#Freeman#and#Company:#New# York,#1997,#Chapter#21.

6d 5d

4d

Cs

Atomic;Radii

Rb

K

Ionic'Radius

Na Li

I Cl

Br

F

Atomic;Number

A;comparison;of;some Atomic and;Ionic radii

Summary'of'the'Chemical'Properties'of'the'Elements ü Group;18;does;not;participate;in;chemical;bonding;in;nature:;noble/inert/rare$ gases. ü Group;1;elements,;the$alkalis,;readily;loses;an;electron;(they;are;called; electropositive);and;are;highly;reactive: § ionic;bonds;rather;than;covalent;ones § bonds;not;as;strong;as;other;elements § soluble;in;aqueous;solutions § ionic;radii;larger;than;other;cations;(+1;charge).; ü Group;2;elements,;the$alkaline$earths,;have;these;same;characteristics,;but; somewhat;moderated.; ü Group;17;elements,;the$halogens,;are;highly;electronegative;and;readily;accept; an;electron: § highly;reactive § form;ionic;bonds § soluble § ionic;radii;larger;than;more;highly;charged;anions.;

Summary'of'the'Chemical'Properties'of'the'Elements ü Elements;of;Groups;13-16;tend;to;form;bonds;that;are;predominantly;covalent: § less;reactive;and;less;soluble;(except;where;they;form;soluble;radicals,;such; as;SO42–);than;Group;1,;2,;&;17;elements. ü The$transition$metals are;a;varied;lot.; § Many;form;strong;bonds;(generally;with;O;in;nature);and;are;fairly; insoluble,;particularly;the;highly;charged;ones.; § Some,;the;‘noble;metals’ (Ru,;Rh,;Pd,;Os,;Ir,;Pt);in;particular,;tend;to;be;very; unreactive;and;insoluble.; ü The$rare$earths are;of;interest;because: § all;have;3;electrons;in;the;6s;outer;orbital, § they;vary;only;by;the;number;of;electrons;in;the;4f;shell.; Their;bonding;behavior;is;thus;quite;similar.;;They;vary;systematically;in;ionic; radius,;which;makes;them;of;great;geochemical;interest.

Appendix'1:'Filling'the'orbitals. Because;each;orbital;corresponds;to;a;unique;set;of;the;first;3;quantum;numbers,;only;2;electrons;may;occupy;a; given;orbital,;and;then;only;if;they;have;different;spins.

§ Each;shell;corresponds;to;a;different;value;of;the;principal;quantum;number.;;The;periodic;nature;of;chemical; properties;reflects;the;filling;of;successive;shells;as;additional;electrons;(and;protons);are;added.;;Each;shell; corresponds;to;a;‘period’,;or;row,;in;the;periodic;table.

§ The;first;shell;(the;K;shell);has;one;subshell,;the;1s,;consisting;of;a;single;orbital;(with;quantum;numbers;n=1,;l=0,; m=0).;;The;1s;orbital;accepts;up;to;2;electrons.;;Thus;period;1;has;2;elements:;H;and;He.;

§ If;another;electron;and;proton;are;added,;the;electron;is;added;to;the;first;orbital,;2s,;of;the;next;shell;(the;L; shell).;;Such;a;configuration;has;the;chemical;properties;of;Li,;the;first;element;of;period;2.;;The;second;shell;has;2; subshells,;2s;(corresponding;to;l=0);and;2p;(corresponding;to;l=1).;;The;p;subshell;has;3;orbitals;(which;correspond; to;values;for;m;of;-1,;+1,;and;0),;px,;py,;and;pz,;so;the;L;shell;can;accept;up;to;8;electrons.;;Thus;period;2;has;8; elements.

§ There;are;some;complexities;in;the;filling;of;orbitals;beyond;the;L;shell.;;In;the;M;shell,;which;corresponds;to; period;3,;there;is;the;possibility;of;putting;electrons;in;the;d;subshell;(l=2),;but;this;is;energetically;less;favorable; than;electrons;going;in;the;subsequent;shell.;;Thus;the;3d;subshell;is;vacant;in;period;3;element;in;their;ground; states,;and;in;the;first;2;elements;of;period;4.;;Only;when;the;4s;orbital;is;filled;do;electrons;begin;to;fill;the;3d; orbitals.;;The;5;3d;orbitals;are;filled;as;one;passes;up;the;first;transition;series;metals,;Sc;through;Zn.;;This;results;in; some;interesting;chemical;properties.

§ Similarly,;the;second;and;third;transition;series;metals;correspond;to;filling;of;the;4d;and;5d;orbitals.;;The; Lanthanide;and;Actinide;rare;earth;elements;correspond;to;the;filling;of;the;4f;and;5f;shells;are;filled;(again; resulting;in;some;interesting;properties).

Appendix'1bis:'Filling'the'Orbitals. 1 2

Main;group;elements

2

P;1:;1s

8

P;2:;2s,;2p

8

P;3:;3s,;3p

18

P;4:;4s,;3d,;4p

18

P;5:;5s,;4d,;5p P;6:;6s,;4f,;5d,;6p

32

P;7:;7s,;5f,;6d,;6p

32$(17)

Inner;transition;series:;REE Actinide;series

4

Transition;elements 3

Appendix'2:'Interactive'Periodic'Table

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