2 - 1 CH110 Chapter 4: Atoms & Elements Elements & Symbols The Periodic Table Atomic Structure Isotopes Electron Energy Levels

2 - 2 CH110 Each element is assigned a unique symbol 1-2 letters; 1st is capitalized Atomic Symbols Bromine Nickel Hydrogen Nitrogen Aluminum

2 - 3 CH110 Atomic Symbols The original name is often of Latin or Greek origin Potassium (Kalium) Lead (Plumbum) Sodium (Natrium) Iron (Ferrum) Silver (Argentum) Gold (Aurum)

2 - 4 CH110 Some of the elements whose symbols are derived from other languages Copper (Cuprum)Cu Gold (Aurum)Au Iron (Ferrum)Fe Lead (Plumbum)Pb Mercury (Hydrargyrum)Hg Potassium (Kalium)K Silver (Argentum)Ag Sodium (Natrium)Na Tin (Stannum)Sn Tungsten (Wolfrum)W Atomic Symbols

2 - 5 CH110 Elements with same starting letter, get second letter added to the symbol Atomic Symbols Chlorine Chromium Calcium Carbon CobaltCopper (Cu)

2 - 6 CH110 Periodic Table: Groups H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTa He RnAtPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNiCoFeMnCrV InXeITeSbSn GaKrBrSeAsGe AlArClSPSi BNeFONC I A III B IVB V B VIB VIIB VIII B IB IIB Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es Alkali Metals Alkaline Earth Metals HalogensHalogens Noble gases III A IV A V A VI A VIIA VIIIA II A Transition Metals

2 - 7 CH110 He Rn XeI KrBrSe ArClS NeFO P NC H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTaPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNiCoFeMnCrV InSbSn GaGe Al Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es At Te As Si B Periods are assigned numbers Periods are assigned numbers Periodic Table: Periods

2 - 8 CH110 At Te As Si B He Rn Xe I KrBrSe ArClS NeFO P NC H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTaPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNi Co FeMnCrV InSbSn GaGe Al Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es MetalsMetals Lustrous, malleable and ductile. Conductors (heat & electricity) Solids at room temp (except Hg) Lose electrons to non-metals. Lustrous, malleable and ductile. Conductors (heat & electricity) Solids at room temp (except Hg) Lose electrons to non-metals.

2 - 9 CH110 He Rn XeI KrBrSe ArClS NeFO P NC H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTaPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNiCoFeMnCrV InSbSn GaGe Al Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es At Te As Si B Non-metalsNon-metals Gasliquidsolid (dull, brittle) Gas, liquid, solid (dull, brittle) Poor conductors = Insulators Many are diatomic molecules. Gain e’s from metals Share e’s with other non-metals Gasliquidsolid (dull, brittle) Gas, liquid, solid (dull, brittle) Poor conductors = Insulators Many are diatomic molecules. Gain e’s from metals Share e’s with other non-metals

CH110 He Rn Xe I KrBrSe ArClS NeFO P NC H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTaPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNiCoFeMnCrV InSbSn GaGe Al Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es At Te As Si B MetaloidsMetaloids Intermediate properties Semi conductors Intermediate properties Semi conductors

CH110 H Li Na Cs Rb K TlHgAuHfLsBa Fr PtIrOsReWTaPoBiPb Be Mg Sr Ca CdAgZrYPdRhRuTcMoNb AcRa ZnCuTiScNi Co FeMnCrV InSn Ga Al Gd Cm Tb Bk Sm Pu Eu Am Nd U Pm Np Ce Th Pr Pa Yb No Lu Lr Er Fm Tm Md Dy Cf Ho Es He Rn XeI KrBrSe ArClS NeFO P NC Sb Ge At Te As Si B MetaloidsMetaloids MetalsMetals Non-metalsNon-metals

CH110 A model of matter Atom Atom - The smallest unit of an element that is still that element. Molecule Molecule -The smallest unit of a pure substance that is still that substance. May contain > 1 atom or element May contain > 1 atom or element. ie. Aluminum (Al) ie. Water (H 2 O)

CH110 & neutrons Structure of the atom Nucleus = + Small, dense, + charge in the center of an atom. containsprotons

CH110 Structure of the atom Nucleus Electrons - - charged particles that surround the nucleus. Electrons nucleusorbitals Electrons move around nucleus in orbitals.

CH110 Structure of the atom nucleus The nucleus is a small part of an atom. If the nucleus was the size of a marble, the atom would fill a football stadium. The nucleus would weigh over 10,000 tons.

CH110 The atomic symbol X A Z A A = Atomic mass (amu) # protons + # neutrons = # protons + # neutrons Z Z = Atomic number # protons# electrons = # protons = # electrons

CH110 The atomic symbol X 12 6 A A = Atomic mass # protons + # neutrons = # protons + # neutrons Z Z = Atomic number # protons# electrons = # protons = # electrons

CH110 The atomic symbol C 12 6 A A = Atomic mass # protons + # neutrons = # protons + # neutrons Z Z = Atomic number # protons# electrons = # protons = # electrons

CH110 The atomic symbol Na A A = Atomic mass = p + n = 23 Z Z = Atomic # = p = 11 Sodium

Ag Silver 47 Atomic number Name of the element Elemental Symbol Atomic mass (weight) Atomic weightaverage Atomic weight = The average, relative mass of an atom in an element. Why is the atomic weight on the tables not a whole #?

CH110 Isotopes of Hydrogen Isotopes = Isotopes = Atoms of the same element but having different masses H H H Protium99.99% Deuterium0.01% Tritium Trace %

CH110 Isotopes of Hydrogen Isotopes = Isotopes = Atoms of the same element but having different masses H H H Average Atomic weight Average Atomic weight of Hydrogen amu = amu

CH Isotopes of Carbon - Average Atomic weight amu Average Atomic weight of C= amu 98.89% C 6 12 C 6 13 C % Trace %

CH110 Radioactive Isotopes C H - Nucleus is unstable So falls apart (decays) Giving radioactive particles

CH110 The atomic symbol & isotopes Determine the number of protons, neutrons and electrons in each of the following. P 3115 Ba U

CH110 Atomic Structure Symbol At# Mass P N e- ____ ____ ____ 4 5 ___ Cl ____ 37 ___ ___ ___ Si ____ ____ ___ 14 ___ Be

CH110 Electron arrangement Electrons fill layers around nucleus Low  High Electrons fill layers around nucleus Low  High Shells = Energy levels 2412 Mg A new layer is added for each row or period in the table. A new layer is added for each row or period in the table.

CH11011H 73Li 42He IA IIA 94Be

CH110115B 11H 73Li IA IIA IIIA 94Be

CH110115B 126C 137N IIIA IVA VA

CH11011H 73Li 42He 94Be 2010Ne 2311 Na 2412 Mg 4018 Ar IA IIA VIIIA

CH Mg 11H 73Li 2311 Na 94Be 115B 2713 Al Valence electrons Where most chemical Reactions occur.1122 Inner electrons Inner electrons: No rxns if normal conditions.

CH110 Inner vs. valence electrons Valence electrons This is where most chemical reactions occur. Inner electrons Not much happens here under normal conditions. With added energy inner electrons jump to higher levels, then fall back giving E higher levels, then fall back giving E

CH11011H 73Li 42He 94Be 2010Ne 2311 Na 2412 Mg 4018 Ar

CH11011H 73Li 2311 Na Electron dot (Lewis) Structures Show only Valence Electrons H Li Na K