TRENDS IN THE PERIODIC TABLE

TRENDS IN THE PERIODIC TABLE ATOMIC RADIUS ANGSTROMS UNKNOWN MELTING POINT KELVIN UNKNOWN 0.00-0.50 0.50-0.75 0.75-1.00 1.00-1.25 1.25-1.50 0-200 200-400 400-700 700-1000 1.50-1.75 1000-1500 1.75-2.00 2.00-2.25 2.25-2.60 1500-2000 2000-3000 3000-4000 Atomic radius decreases across a period as nuclear charge increases but shielding effects remain approximately constant, resulting in electrons being drawn closer to the nucleus. Atomic radius increases down a group as valence electrons become increasingly distant from the nucleus, and shielding also increases. This leads to a increase in atomic radius despite the increasing nuclear charge down a group. Metallic bonded and macromolecular substances tend to have high melting points. For both, this is due to the fact that the bonds require a lot of energy to break. The majority of non-metals have a simple molecular structure. Simple molecular substances have low melting points as only weak intermolecular forces must be overcome in order to melt them. Strength of these is determined by the size of the molecule. ELECTRONEGATIVITY PAULING SCALE UNKNOWN IONISATION ENERGY KILOJOULES PER MOLE UNKNOWN 0.75-1.00 0-500 1.00-1.25 500-600 1.25-1.50 600-700 1.50-1.75 700-800 1.75-2.00 800-1000 2.00-2.50 1000-1500 2.50-3.00 1500-2000 3.00-4.00 2000-2500 Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons. Generally, electronegativity increases moving towards the top right of the Periodic Table. This increase in electronegativity across a period is due to the increased nuclear charge and approximately constant shielding effects resulting in a greater force of attraction to the nucleus of the atom felt by the bonding electrons. The first ionisation energy generally increases from left to right across a period, as the electron is drawn closer to the nucleus by the increased nuclear charge and becomes harder to remove. Electrons in p orbitals are slightly easier to remove than those in s orbitals of the same energy level. Paired electrons in the same orbital can lead to repulsion, again making an electron easier to remove. Both of these factors can lead to lower than expected first ionisation energies. 2014 COMPOUND INTEREST - WWW.COMPOUNDCHEM.COM

3 Li Lithium Group 1 - The Alkali Metals THE GROUP 1 ELEMENTS ARE SHINY, SOFT, AND HIGHLY REACTIVE METALS, NONE OF WHICH OCCUR NATURALLY AS FREE ELEMENTS 11 Na Sodium 19 K Potassium 37 Rb Rubidium 55 Cs Caesium 87 Fr Francium MELTING POINTS 200 0 Li Na K 0 0 200 200 180.5 C 97.7 C 63.4 C 200 0 Rb Cs Fr 0 0 200 200 39.5 C 28.4 C 27.0 C K A L L G R O U P 1 M E TA L S HAVE ONE VALENCE ELECT RON THE REACTIVITY GROUP 1 METALS INCREASES DOWN THE GROUP A S T H E OU T E R E L E C T R O N G E T S F U R T H E R F R O M T H E N U C L E U S & BECOMES EASIER TO REMOVE T H E A L K A L I M E T A L S R E A C T W I T H W A T E R T O F O R M METAL HYDROXIDES LiOH NaOH KOH RbOH CsOH A L K A L I M E T A L S R E A C T W I T H OXYGEN TO F O R M METAL OXIDES A L K A L I M E T A L S R E A C T W I T H HALOGENS TO FORM IONIC SALTS Na + Cl - Na + Cl - Cl - Na + Cl - Na + Na + Cl - Na + Cl - Cl - Na + Cl - Na + U S E S O F T H E A L K A L I M E T A L S LITHIUM SODIUM POTASSIUM RUBIDIUM & CAESIUM ANTI DEPRESSANTS BATTERIES STREET LAMPS TABLE SALT FERTILISERS SOAPS ATOMIC CLOCKS FRANCIUM RADIOACTIVE 2013 COMPOUND INTEREST - WWW.COMPOUNDINTEREST.COM

4 Be Beryllium Group 2 - The Alkaline Earth Metals THE GROUP 2 ELEMENTS ARE SHINY, SILVERY-WHITE, AND SOMEWHAT REACTIVE METALS, SOME OF WHICH OCCUR NATURALLY AS FREE ELEMENTS 12 Mg Magnesium 20 Ca Calcium 38 Sr Strontium 56 Ba Barium 88 Ra Radium MELTING POINTS 1500 Be Mg Ca 0 0 1500 0 1500 1278 C 650 C 839 C Sr Ba Ra 0 1500 0 1500 0 1500 764 C 725 C 700 C Ca ALL GROUP 2 METALS HAVE TWO VALENCE ELECTRONS THE REACTIVITY GROUP 2 METALS INCREASES DOWN THE GROUP AS THE OUTER ELECTRONS GET FURTHER FROM THE NUCLEUS & BECOME EASIER TO REMOVE THEY ARE LESS REACTIVE THAN GROUP 1 THE ALKALINE EARTH METALS REACT WITH WATER TO FORM METAL HYDROXIDES... GROUP 2 METALS R E A C T W I T H OXYGEN TO FORM METAL OXIDES GROUP 2 METALS R E A C T W I T H HALOGENS TO FORM METAL HALIDES BERYLLIUM MAGNESIUM CALCIUM STRONTIUM BARIUM EMERALDS TELESCOPE MIRRORS M(OH) 2 USES ALKALINE EARTH METALS ALLOY WHEELS FLARES BONES R A D I U M BLACKBOARD CHALK E X C E P T FIREWORKS TREATING OSTEOPOROSIS FOR Be WHICH HAS A PROTECTIVE OXIDE LAYER PREVENTING R E A C T I O N RADIUM IS A RADIOACTIVE E L E M E N T WHICH USED TO BE USED TO MAKE GLOW IN THE D A R K P A I N T RAT POISON GLASSMAKING

5 B Boron Group 3 - The Icosagens EXCEPT FOR BORON, THE GROUP 3 ELEMENTS ARE ALL METALS, KNOWN AS POOR METALS DUE TO THEIR LOW MELTING POINTS & HARDNESS 13 Al Aluminium 31 Ga Gallium 49 In Indium 81 Tl Thallium 113 Uut Ununtrium GALLIUM 30 C MELTING POINTS Al INDIUM 156 C THALLIUM 303 C ALUMINIUM 660 C BORON 2076 C BORON IS A METALLOID AND THE O N L Y NON-METAL IN GROUP 3 ALL GROUP 3 ELEMENTS HAVE THREE VALENCE ELECTRONS G A L L I U M I S S O L I D AT ROOM TEMPERATURE BUT IS LIQUID AT A LARGER RANGE O F T E M P E R A T U R E S THAN ANY OTHER ELEMENT SOLID LIQUID GAS 0K 303K 2676K 3600K 47+28+8+5+12+A Al Fe Other Si U S E S O F T H E I C O S A G E N S BORON ALUMINIUM GALLIUM INDIUM THALLIUM GLASSWARE DETERGENT 8.1% O G R O U P 3 E L E M E N T S REACT WITH O X Y G E N T O F O R M METAL OXIDES M 2 O 3 DRINK CANS AIRCRAFT BODIES A L U M I N I U M I S THE THIRD MOST ABUNDANT ELEMENT IN THE EARTH S CRUST A N D T H E M O S T ABUNDANT METAL ELECTRONIC COMPONENTS 1 GRAM THE AVERAGE LETHAL DOSE FOR THE TOXIC ELEMENT T H A L L I U M TOUCH SCREENS RAT POISON

6 C Carbon Group 4 - The Crystallogens THE GROUP 4 ELEMENTS ARE A MIX OF METALS, METALLOIDS & NON-METALS, AND SHOW CONSIDERABLE DIVERSITY IN THEIR PROPERTIES 14 Si Silicon 32 Ge Germanium 50 Sn Tin 82 Pb Lead 114 Fl Flerovium TIN 232 C MELTING POINTS Si LEAD 327 C GERMANIUM 937 C SILICON 1410 C EXPOSURE T O L E A D CAN CAUSE LEAD POISONING CARBON 3730 C ALL GROUP 4 ELEMENTS H A V E FOUR VALENCE ELECTRONS 8 THE NUMBER OF ALLOTROPES OF CARBON INCLUDING DIAMOND, GRAPHITE & BUCKMINSTER FULLERINE SILICON IS THE SECOND MOST ABUNDANT ELEMENT IN THE EARTH S CRUST AT 25.7% FLEROVIUM IS ONE MAN-MADE ELEMENTS DISCOVERED IN 1999 10 112 Sn 114 Sn 115 Sn 116 Sn 117 118 Sn Sn 119 Sn 120 Sn 122 Sn 124 Sn TIN IS THE ELEMENT WITH THE LARGEST NUMBER OF STABLE ISOTOPES THE GROUP FOUR ELEMENTS FORM HYDRIDES WITH H Y D R O G E N U S E S O F T H E C R Y S T A L L O G E N S CARBON SILICON GERMANIUM TIN LEAD DIAMONDS CARBON DATING EH 4 T E T R A H A L I D E S WITH HALOGENS EX 4 AND A VARIETY OF OXIDES WITH OXYGEN GLASS ELECTRONICS MICROSCOPE & CAMERA LENSES CARBON MAKES UP 18.5% HUMAN BODY IT ALSO FORMS ORGANIC COMPOUNDS THE STUDY OF WHICH IS KNOWN AS ORGANIC CHEMISTRY TIN CANS RADIATION SHIELDING LEADED PETROL

7 N Nitrogen Group 5 - The Pnictogens THE GROUP 5 ELEMENTS ARE ALL SOLIDS APART FROM NITROGEN, AND ARE A MIX OF NON-METALS, METALLOIDS AND A METAL 15 P Phosphorus 33 As Arsenic 51 Sb Antimony 83 Bi Bismuth 115 Uup Ununpentium NITROGEN -210 C MELTING POINTS PHOSPHORUS 44 C P BISMUTH 271 C ARSENIC 603 C ANTIMONY 631 C ANCIENT EGYPTIANS U S E D T H E ANTIMONY COMPOUND CALLED STIBNITE AS E Y E M A K E - U P 0. 0 6 GRAMS BISMUTH IS THE ONLY METALLIC ELEMENT PRESENT IN GROUP FIVE ALL GROUP 5 ELEMENTS H A V E FIVE VALENCE ELECTRONS LETHAL DOSE OF ARSENIC 78+21+1+A O Other 78% THE PNICTOGENS FORM PNICTIDES WITH MOST ELEMENTS PHOSPHORUS CONTAINING CALCIUM PHOSPHATE COMPOUNDS MAKE UP O F H U M A N B O N E U S E S O F T H E P N I C T O G E N S NITROGEN PHOSPHORUS ARSENIC ANTIMONY BISMUTH EXPLOSIVES FERTILISERS N PNICTOGENS FORM: HYDRIDES WITH HYDROGEN OXIDES WITH OXYGEN HALIDES WITH HALOGENS N I T R O G E N I S THE MOST ABUNDANT ELEMENT IN THE EARTH S ATMOSPHERE SAFETY MATCHES SMOKE BOMBS AMMUNITION MANUFACTURING 70% FLAME RETARDENTS COSMETICS X-RAY SHIELDS MEDICINES

8 O Oxygen Group 6 - The Chalcogens THE GROUP 6 ELEMENTS ARE A MIX OF ELECTRONEGATIVE NON-METALS & METALLOIDS COMMONLY ASSOCIATED WITH METAL BEARING MINERALS 16 S Sulphur 34 Se Selenium 52 Te Tellurium 84 Po Polonium 116 Lv Livermorium OXYGEN -219 C MELTING POINTS SULPHUR 120 C S SELENIUM 221 C POLONIUM 254 C TELLURIUM 450 C ALL SOLID CHALCOGENS ARE SOFT AND DON T CONDUCT HEAT WELL ALL GROUP 6 ELEMENTS HAVE SIX VALENCE ELECTRONS ALL THE GROUP 6 ELEMENTS F O R M - 2 I O N S W H E N R E A C T I N G W I T H ELECTROPOSITIVE METALS SULPHUR DIOXIDE REACTS WITH WATER VAPOUR TO FORM SULPHURIC ACID AND CAUSE ACID RAIN OXYGEN MAKES UP 65% HUMAN BODY ALLOTROPES OXYGEN NINE O 2 O 3 O 4 O 8 SELENIUM FIVE MAINLY Se 8 OXYGEN SULPHUR SELENIUM TELLURIUM POLONIUM MAKING STEEL ROCKET FUEL SULPHUR TWENTY S 2 S 3 S 4 S 8 POLONIUM T W O α-po & ß-Po U S E S O F T H E C H A L C O G E N S GUNPOWDER SULPHURIC ACID PHOTOCOPIERS GLASS-MAKING ALL COMPOUNDS OF HYDROGEN WITH CHALCOGENS ARE APART FROM WATER CD-RW DISCS SOLAR PANELS H TOXIC O SELENIUM, TELLURIUM & POLONIUM A R E A L L METALLOIDS H O X Y G E N IS THE ONLY G A S E O U S CHALCOGEN α ALPHA PARTICLE GENERATOR IN RESEARCH

9 F Fluorine Group 7 - The Halogens GROUP 7 IS THE ONLY GROUP THAT CONTAINS ELEMENTS IN ALL THREE STATES OF MATTER. THEY ARE ALL REACTIVE NON-METALS 17 Cl Chlorine 35 Br Bromine 53 I Iodine 85 At Astatine 117 Uus Ununseptium IODINE & ASTATINE SOLIDS AT ROOM TEMPERATURE Cl BROMINE LIQUID AT ROOM TEMPERATURE FLUORINE & CHLORINE GASES AT ROOM TEMPERATURE ALL GROUP 7 ELEMENTS HAVE SEVEN VALENCE ELECTRONS THE REACTIVITY HALOGENS DECREASES DOWN THE GROUP AS IT BECOMES HARDER TO A D D A N E L E C T R O N 1 GRAM ESTIMATED THE HALOGENS ALL FORM DIATOMIC MOLECULES EXCEPT FOR ASTATINE AMOUNT OF ASTATINE IN THE EARTH S CRUST AT ANY ONE TIME THE HALOGENS R E A C T W I T H OXYGEN TO FORM HALOGEN OXIDES THE HALOGENS R E A C T W I T H METALS TO FORM METAL HALIDES HYDROFLUORIC ACID LEACHES CALCIUM FROM BONES AND CAN CAUSE VERY PAINFUL BURNS IT ALSO DISSOLVES G L A S S FLUORINE CHLORINE BROMINE IODINE TOOTHPASTE REFRIDGERANT GASES U S E S O F T H E H A L O G E N S BLEACH CHEMICAL WARFARE THE HALOGENS ARE USED AS OXIDISING AGENTS WHILST HALIDE IONS ARE USED AS REDUCING AGENTS F 2 I - FIRE RETARDANT MATERIALS IONS DISINFECTANTS

2 He Helium Group 8 - The Noble Gases THE GROUP 8 ELEMENTS ARE ALL ODOURLESS, COLOURLESS, MONOATOMIC GASES WITH A VERY LOW CHEMICAL REACTIVITY 10 Ne Neon 18 Ar Argon 36 Kr Krypton 54 Xe Xenon 86 Rn Radon HELIUM -269 C BOILING POINTS NEON -246 C Ar ARGON -186 C KRYPTON -152 C XENON -107 C THE NOBLE GASES ARE ALL MONOATOMIC AND RARELY FORM COMPOUNDS ALL GROUP 8 ELEMENTS HAVE A FULL OUTER SHELL OF ELECTRONS THE GROUP 8 ELEMENTS ARE V E R Y U N R E A C T I V E AS THEY ALREADY HAVE A FULL VALENCE ELECTRON SHELL -269 C HELIUM RADON -62 C HAS THE LOWEST BOILING POINT OF ALL ELEMENTS IN THE PERIODIC TABLE THE COLOURS IN NEON SIGNS ARE CAUSED BY IONISED NOBLE GASES He Ne Ar Kr Xe 1 2 3 H He O 75% 23% 1% HELIUM I S T H E SECOND MOST ABUNDANT ELEMENT IN THE UNIVERSE R A D O N I S RADIOACTIVE AND CAN ENTER HOMES THROUGH BASEMENTS AFTER RADIOACTIVE DECAY OF ROCKS BELOW THE EARTH U S E S O F T H E N O B L E G A S E S HELIUM NEON ARGON KRYPTON XENON BALLOONS NEON NEON LIGHTS REFRIGERANT MEDICAL LASERS LIGHT BULBS CAMERA FLASHES 222 Rn MEDICAL IMAGING

The Transition Metals A LARGE GROUP OF METALS IN THE CENTRE PERIODIC TABLE, THEY ARE LESS REACTIVE THAN THE GROUP 1 & 2 METALS, AND HAVE HIGH MELTING POINTS & DENSITIES 21 Sc Scandium 22 Ti Titanium 23 V Vanadium 24 Cr Chromium 25 Mn Manganese 26 Fe Iron 27 Co Cobalt 28 Ni Nickel 29 Cu Copper 30 Zn Zinc 39 Y Yttrium 40 Zr Zirconium 41 Nb Niobium 42 Mo Molybdenum 43 Tc Technetium 44 Ru Ruthenium 45 Rh Rhodium 46 Pd Palladium 47 Ag Silver 48 Cd Cadmium 72 Hf Hafnium 73 Ta Tantalum 74 W Tungsten 75 Re Rhenium 76 Os Osmium 77 Ir Iridium 78 Pt Platinum 79 Au Gold 80 Hg Mercury 3422 C TUNGSTEN HAS THE HIGHEST MELTING POINT OF ANY METALLIC E L E M E N T TRANSITION METALS FORM Co 2+ Cr 3+ Fe 3+ Fe 2+ Cu 2+ Mn 7+ Mn 2+ Ni 2+ C O L O U R E D C O M P O U N D S N S THERE ARE THREE MAGNETIC METALS IRON, COBALT AND NICKEL MERCURY IS THE ONLY LIQUID METAL AT ROOM TEMPERATURE Hg UNLIKE GROUP 1 & 2 METALS TRANSITION METALS CAN FORM CO-ORDINATION COMPLEXES WITH OTHER ATOMS & MOLECULES TRANSITION METALS HAVE VARIOUS OXIDATION STATES -3-2 -1 +1 +2 +3 +4 +5 +6 +7 M A N G A N E S E H A S T E N P O S S I B L E OXIDATION STATES COPPER, SILVER & GOLD ARE KNOWN AS THE C O I N A G E M E T A L S Cu Ag Au

The Lanthanides ALSO KNOWN AS THE RARE EARTH ELEMENTS, THE LANTHANIDES ARE SILVER, METALLIC ELEMENTS, AND CAN BE FOUND IN MINERALS IN THE EARTH S CRUST 57 La Lanthanum 58 Ce Cerium 59 Pr Praseodymium 60 Nd Neodymium 61 Pm Prometheum 62 Sm Samarium 63 Eu Europium 64 Gd Gadolinium 65 Tb Terbium 66 Dy Dysprosium 67 Ho Holmium 68 Er Erbium 69 Tm Thulium 70 Yb Ytterbium 71 Lu Lutetium THE LANTHANIDES ALL FORM STABLE +3 IONS THE LANTHANIDES HAVE ELECTRONS IN THE 4f ORBITAL LEADING TO THE LANTHANIDE CONTRACTION $ PHOSPHORESCENT EUROPIUM & TERBIUM COMPOUNDS ARE USED IN ANTI-COUNTERFEIT BANK NOTES Pr 3+ Nd 3+ Pm 3+ Sm 3+ Tm 3+ Ce 4+ Eu 3+ Dy 3+ Eu 2+ Tb 3+ Ho 3+ Er 3+ SEVERAL LANTHANIDES FORM COLOURED IONS NEODYMIUM ALLOYS ARE USED TO MAKE THE STRONGEST PERMANENT MAGNETS FOUND IN LOUDSPEAKERS AND IN HEADPHONES Eu LANTHANIDES REACT WITH O X Y G E N TO GIVE OXIDES Ln 2 O 3 SOME LANTHANIDES ARE USED AS COLOUR PHOSPHORS IN SOME TV SCREENS Eu Ce Tb Gd LANTHANIDE COMPOUNDS ARE USED TO COLOUR CERAMICS & G L A S S Yb Er Tb Lu Dy Gd Tm Ho MANY LANTHANIDES W E R E F O U N D I N MINERAL ORES FROM A MINE IN THE VILLAGE OF Y T T E R B Y, S W E D E N YTTERBIUM, ERBIUM, TERBIUM & YTTRIUM ARE ALL NAMED AFTER YTTERBY IN 2010, CHINA FOR95% ACCOUNTED OF GLOBAL RARE EARTH ELEMENT PRODUCTION SAMARIUM & COBALT ALLOY IS USED TO MAKE THE MAGNETS FOUND IN ELECTRIC GUITAR PICK-UPS 2014 COMPOUND INTEREST - WWW.COMPOUNDCHEM.COM

The Actinides THE ACTINIDES ARE DENSE, RADIOACTIVE METALS, MANY OF WHICH ARE UNSTABLE, AND THE MAJORITY OF WHICH ARE MADE SYNTHETICALLY 89 Ac Actinium 90 Th Thorium 91 Pa Protactinium 92 U Uranium 93 Np Neptunium 94 Pu Plutonium 95 Am Americium 96 Cm Curium 97 Bk Berkelium 98 Cf Californium 99 Es Einsteinium 100 Fm Fermium 101 Md Mendelevium 102 No Nobelium 103 Lr Lawrencium DATES OF DISCOVERY ACTINIDES NATURALLY ABUNDANT SYNTHETICALLY PRODUCED 1820 Th U Ac Pa Np Pu Am Cm Bk Cf Es Fm Md Nb Lr 1970 1829 1841 1899 1930 1940 1944 1949 1950 1952 1955 1958 1961 THE ACTINIDES ALL FORM STABLE +3 IONS BERKELIUM IS THE Bk RAREST NATURALLY OCCURRING ELEMENT (NO MORE THAN A FEW ATOMS AT A T I M E I N U R A N I U M D E P O S I T S ) U 3+ U 4+ U 5+ U 6+ SOME ACTINIDES HAVE OXIDATION STATES OF VARYING COLOURS Pu 3+ Pu 4+ Pu 5+ Pu 6+ Pu 7+ URANIUM & PLUTONIUM ARE USED FOR NUCLEAR POWER THORIUM CAN FORM MORE COVALENT BONDS THAN ANY OTHER ELEMENT Th 14 THORIUM IS A PYROPHORIC ELEMENT (IGNITES SPONTANEOUSLY IN AIR) CURIUM IS SO RADIOACTIVE THAT IT GLOWS PURPLE Cm ACTINIDES NAMED AFTER FAMOUS SCIENTISTS CURIUM MARIE CURIE WON NOBEL PRIZE FOR WORK ON RADIOACTIVITY & ALSO DISCOVERED POLONIUM AND RADIUM EINSTEINIUM ALBERT EINSTEIN DEVELOPED GENERAL THEORY OF RELATIVITY & WON NOBEL PRIZE FOR WORK ON PHOTOELECTRIC EFFECT FERMIUM ENRICO FERMI WON NOBEL PRIZE FOR WORK ON RADIOACTIVITY & ALSO CONSTRUCTED THE FIRST NUCLEAR REACTOR MENDELEVIUM DMITRI MENDELEEV CREATED THE MODERN PERIODIC TABLE & USED IT TO PREDICT PROPERTIES OF UNDISCOVERED ELEMENTS NOBELIUM ALFRED NOBEL THE INVENTOR OF DYNAMITE, & LEFT HIS FORTUNE AFTER HIS DEATH TO FOUND THE NOBEL PRIZES LAWRENCIUM ERNEST LAWRENCE WON A NOBEL PRIZE FOR THE INVENTION CYCLOTRON, A TYPE OF PARTICLE ACCELERATOR 2014 COMPOUND INTEREST - WWW.COMPOUNDCHEM.COM