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A Guided Tour of the Periodic Table. Section 3.2. Using the Periodic Table. Atomic number – the number of protons in the nucleus of an atom or the number of electrons in the nucleus of an atom. ALWAYS TRUE !!!!! The elements are in o rder of Periodic Table b y the # of protons present
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A Guided Tour of the Periodic Table Section 3.2
Using the Periodic Table • Atomic number – the number of protons in the nucleus of an atom or the number of electrons in the nucleus of an atom. • ALWAYS TRUE!!!!! The elements are in order of Periodic Table by the # of protons present in the nucleus.
Using the Periodic Table • Mass number – the TOTAL number of protons and neutrons in the nucleus of an atom; may change.
Using the Periodic Table • Ions: • 1. Ionization – the process of adding electrons to or removing electrons from an atom or group of atoms. • 2. Ion – an atom or group of atoms that has lost or gained one or more electrons and therefore has a net electric charge.
Using the Periodic Table • Ions: Cation – an ion with a positive charge. (Lithium, Li) Li+
Ions Anion – an ion with a negative charge (Flourine, F) F-
Using the Periodic Table • Isotopes- any atoms having the same number of protons but DIFFERENT number of neutrons. • See fig 3-17 on pg 84 in textbook
Charge (if ion) Atomic Mass Symbol Atomic Number
Hydrogen Protons: 1 Neutrons: 0 Electrons: 1 H 1 1
Sodium Protons: 11 Neutrons: 12 Electrons: 11 Na 23 11
EXAMPLE 133 55 How many protons, neutrons and electrons are found in an atom of Cs Atomic number = protons and electrons There are 55 protons and 55 electrons Mass number = sum of protons and neutrons 133 – 55 = 78 There are 78 neutrons
Atomic Mass Unit (AMU) – a quantity equal to 1/12 of the mass of a Carbon-12 atom • Average Atomic Mass- the weighted average of the masses of all naturally occurring isotopes of an element.
Organization of the P.T. • Periodic Law: properties of elements tend to change in a regular pattern when elements are arranged in order of increasing atomic number, or number of protons in their atoms.
The Periodic Table Over 100 years ago, the chemist Mendeleev arranged the known elements in order of increasing atomic mass. He noticed a repeating pattern in the properties of the elements. He designed a table with rows and columns to show the repeating patterns.
The Periodic Table • Mendeleev left blank spaces in his table when the properties of the elements above and below did not seem to match. • The existence of unknown elements was predicted by Mendeleev on the basis of the blank spaces. When the unknown elements were discovered, it was found that Mendeleev had closely predicted the properties of the elements as well as their discovery.
In the Modern Periodic Table . . . • Elements are arranged by increasing atomic numbers. • The term “periodic” part means that similar properties repeat every so often. • There are currently 118 known elements.
Rows of the Periodic Table • The beginning of the row is where the patterns that Mendeleev discovered begin repeating again.
What the table tells you . . . • Each box contains information about one of the elements. - Atomic Number - Chemical Symbol - Name of Element - Atomic Mass • Some tables give more information for each element.
Periodic Table • The color of the box tells you if the state of the element at room temperature and pressure is a solid, liquid, or gas. • Most are solids, some are gases, and two are liquids. • The stair-step line separates metals from non-metals. • Metals are to the left of the stair-step line; non-metals are to the right.
Using the Periodic Table • 1. Period a horizontal row of elements in the periodic table • 2. Determines electron arrangement
Using the Periodic Table • Groups (family) – a vertical column of elements in the periodic table. • Same number of valence electrons in each group therefore they have similar properties. • Examples: Cl (Chlorine) and F (Flourine) These are both Halogens and have very similar properties.
Columns on the Periodic Table There are 18 columns or groups. The elements in each group resemble each other – the react similarly to other substances.
How are elements classified? • A: Metals vs. Nonmetals 1: Elements can be put in various types of categories based on their physical and chemical properties. A common physical property used to classify elements are metallic and nonmetallic properties.
Periodic Table: Metallic arrangement • Layout of the Periodic Table: Metals vs. nonmetals Nonmetals Metals
Periodic Table: The three broad ClassesMain, Transition, Rare Earth Main (Representative), Transition metals, lanthanides and actinides (rare earth)
Metals vs Nonmetals Metallicproperties include: A. Shiny B. Conduct Heat/Electricity C. Ductile/Malleable D. Have a positive Oxidation Number E. Found on the Left/Middle of the Periodic Table
Metals vs Nonmetals Nonmetallic properties include: a. Dull b. Poor conductor of Heat/Electricity (INSULATORS) c. Brittle d. Have a Negative Oxidation Number e. Found on the Right Side of P.T.
Metals vs Nonmetals Some elements have properties of bothmetals and nonmetals and are referred to as metalloids. Metalloids are usually nonmetals that can conduct heat and electricity. The metalloids are located between the metal and nonmetal sides of the periodic table.
Metals vs Nonmetals • There are 109 total elements on the periodic table. • Out of the 109 elements, 84 are metals, 17 nonmetals and 8 metalloids (semiconductors)
Families FAMILIES OF ELEMENTS Elements are put into families based on similarities of chemical properties.
Families Families of Periodic Table a. ALKALI METALS – 1 (IA) b. ALKALINE EARTH METALS – 2 (IIA) c. TRANSITION METALS – 3-12 (B Groups) d. HALOGEN GROUP – 17 (VIIA) e. NOBLE GASES – 18 (VIIIA)
ALKALIE METALS (IA) • Group IA elements on P.T. • With EXCEPTION of Hydrogen (H), they are the MOST Metallic elements on the table. • Best conductors of heat and electricity • Most reactive metals on earth • Never found free, always found in a compound. • ALL HAVE ONLY 1 VALENCE ELECTRON
Alkaline Earth Metals (IIA) • Group IIA on P.T. • Not as reactive as the group IA metals • Still very reactive • Never found free in nature • ALL HAVE 2 VALENCE ELECTRONS
TRANSITION METALS (IIIB – IIB) • A majority of the elements on the periodic table are transition metals. • Names given based on their decreasing metallic characteristics as one moves from the left to the right side of the periodic table.
HALOGENS • Found in group VIIA • Known as the Salt Forming elements • HALO- means “salt forming” • Most reactive nonmetals • NEVER found free in nature • Usually found in salt compounds containing a metal from either alkali or alkaline earth metal families.
NOBLE GASES • Group VIIIA • ALL Nonreactive Nonmetals • Only elements known that have a naturally FULL Valence Shell (Outer energy level) • Since nonreactive, then they will ALWAYS be found FREE in nature and NEVER in a compound.
Periodic Tablee- configuration from the periodic table(To be covered in future chapters) • B • 2p1 H 1s1 He 1s2 F 2p5 Be 2s2 B 2p1 C 2p2 N 2p3 Ne 2p6 O 2p4 Li 2s1 Na 3s1 Mg 3s2 Cl 3p5 Si 3p2 S 3p4 Ar 3p6 Al 3p1 P 3p3 K 4s1 Ca 4s2 Zn 3d10 As 4p3 Be 4p5 V 3d3 Mn 3d5 Fe 3d6 Co 3d7 Sc 3d1 Ti 3d2 Ga 4p1 Ge 4p2 Se 4p4 Cr 4s13d5 Kr 4p6 Ni 3d8 Cu 4s13d10 Sr 5s2 Rb 5s1 Nb 4d3 Ru 4d6 Rh 4d7 Mo 5s14d5 Cd 4d10 Sn 5p2 I 5p5 Xe 5p6 Zr 4d2 Tc 4d5 Y 4d1 In 5p1 Sb 5p3 Te 5p4 Ni 4d8 Ag 5s14d10 Hf 5d2 Cs 6s1 Ta 5d3 Re 5d5 Os 5d6 Ir 5d7 W 6s15d5 La 5d1 Rn 6p6 At 6p5 Ni 5d8 Ba 6s2 Hg 5d10 Tl 6p1 Pb 6p2 Bi 6p3 Po 6p4 Au 6s15d10 Mt 6d7 Bh 6d5 Hs 6d6 Fr 7s1 Rf 6d2 Ra 7s2 Db 6d3 Sg 7s16d5 Ac 6d1
Summary Periodic Table: Map of the Building block of matter Type: Metal, metalloid and Nonmetal Groupings: Representative or main, transition and Lanthanide/Actinides (rare) Family: Elements in the same column have similar chemical property because of similar valence electrons Alkali Metal, Alkaline Earth Metal, halogens, noble gases Period: Elements in the same row have valence electrons in the same shell.
Iron Triad Iron (Fe) Cobalt (Co) Nickel (Ni)
Coinage Elements Copper (Cu) Silver (Ag) Gold (Au)
Liquid @ Room Temp Mercury (Hg) and Bromine (Br)