Topic 3.1 The periodic table 1

Assessment Statements Describe the arrangement of elements in the periodic table in order of increasing atomic number Distinguish between the terms group and period Apply the relationship between the electron arrangement of elements and their position in the periodic table up to Z = Apply the relationship between the number of electrons in the highest occupied energy level for an element and its position in the periodic table. 2

Describe the arrangement of elements in the periodic table in order of increasing atomic number. Development of the Periodic Table Johan Dobereiner Grouped similar elements into groups of 3 (triads) such as chlorine, bromine, and iodine. ( ). John Newlands Found every eighth element (arranged by atomic weight) showed similar properties. Law of Octaves (1863). Dmitri Mendeleev Arranged elements by similar properties but left blanks for undiscovered elements (1869). 3

Dmitri MendeleevDmitri Mendeleev (1869) In 1869 Mendeleev (Russia) and Lothar Meyer (Germany) published nearly identical classification schemes for elements known at the time. The periodic table is based on the similarity of properties and reactivities exhibited by various elements. Later, Henri Moseley ( England, ) established that each element has a unique atomic number, which is how the current periodic table is organized.

Describe the arrangement of elements in the periodic table in order of increasing atomic number. Distinguish between the terms group and period. Development of the Periodic Table Henry Mosley Arranged the elements by increasing atomic number instead of mass (1913) Glen Seaborg Discovered the transuranium elements ( ) and added the actinide and lanthanide series (1945) Elements arranged by increasing atomic number into periods (rows) and groups or families (columns), which share similar characteristics 5

The Periodic Table A map of the building block of matter.

Periodic Table Expanded View The Periodic Table can be arranged by energy sub levels The s-block is Group IA and & IIA, the p-block is Group IIIA - VIIIA. The d-block is the transition metals, and the f- block are the Lanthanides and Actinide metals The Periodic Table can be arranged by energy sub levels The s-block is Group IA and & IIA, the p-block is Group IIIA - VIIIA. The d-block is the transition metals, and the f- block are the Lanthanides and Actinide metals The way the periodic table usually shown is a compressed view. The Lanthanides and actinides (F block)are cut out and placed at the bottom of the table. The way the periodic table usually shown is a compressed view. The Lanthanides and actinides (F block)are cut out and placed at the bottom of the table.

Periodic Table: The three broad Classes Main, Transition, Rare Earth Main (Representative), Transition metals, lanthanides and actinides (rare earth)

Reading the Periodic Table: Classification Nonmetals, Metals, Metalloids, Noble gases

Down the Periodic Table Families are arranged vertically down the periodic table (columns or group, or 1-8 A,B) Families are arranged vertically down the periodic table (columns or group, or 1-8 A,B) These elements have the same number of electrons in the outer most energy level, known as the valence shell. These elements have the same number of electrons in the outer most energy level, known as the valence shell. Alkali Family: 1 e- in the valence shell Alkali Family: 1 e- in the valence shell Halogen Family: 7 e- in the valence shell Halogen Family: 7 e- in the valence shell

Notable Families of the Periodic Table Notable families of the Periodic Table and some important members: Alkali Alkaline (earth) Transition Metals Noble Gas HalogenChalcogens

Describe the arrangement of elements in the periodic table in order of increasing atomic number. Arrangement of the Periodic Table Metals Left side of the periodic table (except hydrogen). High electrical conductivity, high luster, ductile, malleable Alkali metals: Group 1 (1A) Alkaline earth metals: Group 2 (2A) Transition metals: Group B, lanthanide & actinide series Nonmetals Right side of the periodic table Poor conductors and nonlustrous Halogens: Group 17 (7A) Noble gases: Group 18 (0) Metalloids Between metals and nonmetals Properties intermediate between metals and nonmetals 12

Apply the relationship between the electron arrangement of elements and their position in the periodic table. Arrangement of the Periodic Table Noble Gases: Outermost s and p sublevels are filled. Ending configuration is s 2 p 6 (except He) Eight valence electrons (except He) Row number equals energy level Representative Elements: Outermost s and p sublevels are partially filled. Group A elements (1A-7A) 1A (s 1 ); 2A (s 2 ); 3A (s 2 p 1 ); 4A (s 2 p 2 )… Group number equals valence electrons Row number equals energy level Transition Metals Filling the d & f sublevels 13

14 Classification of the Elements

Apply the relationship between the number of electrons in the highest occupied energy level for an element and its position in the periodic table. Shortcut Electron Configuration Electron dot diagrams Group 1A: 1 dotXGroup 5A: 5 dotsX Group 2A: 2 dotsXGroup 6A: 6 dots X Group 3A: 3 dotsXGroup 7A: 7 dotsX Group 4A: 4 dotsXGroup 0: 8 dots (except He)X 15

16 ns 1 ns 2 ns 2 np 1 ns 2 np 2 ns 2 np 3 ns 2 np 4 ns 2 np 5 ns 2 np 6 d1d1 d5d5 d 10 4f 5f Ground State Electron Configurations of the Elements

IB Topic 3: Periodicity 3.3: Chemical properties Discuss the similarities and differences in the chemical properties of elements in the same group. Discuss the changes in nature, from ionic to covalent and from basic to acidic, of the oxides across period 3. 17

Discuss the similarities and differences in the chemical properties of elements in the same group. Alkali Metals Reaction with water 2M (s) + 2H 2 O (l)  2M + (aq) + 2OH - (aq) + H 2 (g) where M represents Li,Na,K,Rb, or Cs 2Na (s) + 2H 2 O (l)  2Na + (aq) + 2OH - (aq) + H 2 (g) Reactivity increases down the group 18

Discuss the similarities and differences in the chemical properties of elements in the same group. Alkali Metals Reaction with halogens 2M (s) + X 2 (g)  2MX (s) where M represents Li,Na,K,Rb, or Cs Where X represents F,Cl,Br, or I 2Na (s) + Cl 2 (g)  2NaCl (s) Reactivity increases down the group 19

Discuss the similarities and differences in the chemical properties of elements in the same group. Halogens Reaction with halide ions Cl 2 reacts with Br - and I - Cl 2 (aq) + 2Br - (aq)  2Cl - (aq) + Br 2 (l) Cl 2 (aq) + 2I - (aq)  2Cl - (aq) + I 2 (s) Br 2 reacts with I- Br 2 (aq) + 2I - (aq)  2Br - (aq) + I 2 (s) I 2 non-reactive with halide ions 20

Discuss the changes in nature, from ionic to covalent and from basic to acidic, of the oxides across period 3. Metallic Oxides in Period 3 Sodium oxide: Na 2 Oionic Magnesium oxide: MgOionic Aluminum oxide: Al 2 O 3 ionic Metalloid oxide in Period 3 Silicon dioxide: SiO 2 covalent Nonmetallic oxides in Period 3 Tetraphosphorus decoxide: P 4 O 10 covalent Sulfur trioxide: SO 3 covalent Dichlorine heptoxide: Cl 2 O 7 covalent 21

Discuss the changes in nature, from ionic to covalent and from basic to acidic, of the oxides across period 3. Acidic/Basic Metallic oxides in Period 3 are basic Sodium oxide: Na 2 O + H 2 O  2 NaOH basic Magnesium oxide: MgO + H 2 O  Mg(OH) 2 basic Aluminum oxide: Al 2 O 3 + H 2 O  2 Al(OH) 3 amphoteric Metalloid oxide in Period 3 is acidic Silicon dioxide:SiO 2 + H 2 O  H 2 SiO 3 acidic Nonmetallic oxides in Period 3 are acidic Tetraphosphorus decoxide: P 4 O H 2 O  4H 3 PO 4 acidic Sulfur trioxide: SO 3 + H 2 O  H 2 SO 4 acidic Dichlorine heptoxide: Cl 2 O 7 + H 2 O  2HClO 4 acidic Argon does not form an oxide 22

Terms to Know Group Period Alkali metals Halogens Ionic radius Electronegativity First ionization energy 23