Chapter 6 The Periodic Table and Periodic Law. Historical Timeline Development of the Periodic...

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Chapter 6Chapter 6

The Periodic Table and Periodic Law

Historical Timeline Development of the

Periodic Table

Thursday and Friday

6.1 Development of the Periodic Table

• Late 1790s

• Antoine Lavoisier

• compiled a list of all elements known at the time- 23 elements

• 1800s- invention of electricity, development of spectrometer, and industrial revolution led to explosion in the number of known elements

• By 1870 there were 70 known elements

• 1864• John Newlands • created law of octaves, which

means that properties repeat every 8th element

• Law doesn’t work for all elements

• 1869

• Meyer and Mendeleev demonstrated a connection between atomic mass and elemental properties

• 1869

• Mendeleev organized 1st periodic table by atomic mass and left blank spaces where undiscovered elements should go- not completely correct

•1913• Moseley arranged elements

according to atomic number• Periodic Law – the periodic

repetition of chemical and physical properties of elements when they are arranged by increasing atomic number

The Modern Periodic Table• Consists of boxes containing

element name, symbol, atomic number, and atomic mass

Friday• We will finish the historical timeline of the periodic

table• We will color the two main sections of the periodic

table:• Representative elements• Transition elements• We will color in the metals and the nonmetals and

the metalloids

• Representative Elements- main group of periodic table (1,2, and 13-18), s and p block; represent a wide range of chemical and physical properties

• Transition Elements- groups 3-12

Classifying the Elements• Metals- elements that are

generally shiny, solids at room temperature, good conductors of heat and electricity, malleable (able to be pounded into thin sheets), and ductile (drawn into wires)

• Nonmetals- generally gases or brittle, dull-looking solids; poor conductors of electricity

• Metalloids- elements with physical and chemical properties of both metals and nonmetals

Monday• We will make a foldable over the different types of

groups in the periodic table

The Families of the modern Periodic Table

• Alkali Metals- Group 1A (1)

• Alkaline Earth Metals- Group 2A (2)

• Both groups are chemically reactive

• Transition Metals- Group B elements (d block)

• Inner Transition Metals- (f block)

• Halogens- Group 7A (17); highly reactive

• Noble Gases- Group 8A (18); extremely unreactive

Classifying the Elements• S-block elements

–groups 1A and 2A

–Holds a maximum of two electrons

• P-block elements group 3A through 8A, or 13-18

Holds a maximum of 6 electrons

• d-block elements– contains transition metals

– largest block– holds maximum of 10 electrons

• f-block elements– contains inner transition metals

– lanthanide and actinide series

– holds maximum of 14 electrons

Tuesday - Exploration Activity• Lab over the periodic trends of the Periodic

Table

Wednesday• We will do trends on the periodic table• Compare our notes to he lab from Tuesday

6.3 Periodic Trends• Atomic Radius

generally increases from right to left and increases from top to bottom of the periodic table

• Adaptive Curriculum Clip

Atomic Size

•Ionic Radius- positive ions decrease from left to right until group 3A (13), then negative ions decrease until 8A (18); generally increases from top to bottom

•Ion- atom or bonded group of atoms that has a positive or negative charge

Cation –positively charged ion (lost electron)–Will decrease radius because of loss of outer energy level–Are in groups 1-13

Anions–negatively charged ion (gained

electron)–will increase radius because

protons “pulling in” are the same and with extra electrons they repel each other and spread out

–groups 14-18

Atomic and Ionic radius follow the

same trend!!

Ionization Energy

• energy required to remove an electron from a gaseous atom

• generally decreases from right to left and decreases from top to bottom

Electronegativity• indicates the relative ability of its

atoms to attract electrons in a chemical bond

• decreases from right to left and decreases from top to bottom

Follows the same trend as electronegativity!!

Thursday• We will finish our lab• We will finish our review and check it in

class

Friday• We will test on Friday