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UNIT : Matter. TOPIC : Periodic Table of Elements. Objectives: Lesson 2 of 4 You will learn what the periodic table is and how it is arranged and organized To know the difference between groups and periods in the periodic table
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UNIT: Matter TOPIC: Periodic Table of Elements Objectives: Lesson 2 of 4 • You will learn what the periodic table is and how it is arranged and organized • To know the difference between groups and periods in the periodic table • To understand the reactivity and properties of the different groups on the periodic table • To become familiar with the 7 naturally occurring diatomic molecules
Quickwrite Answer one of the questions below 1-2 sentences: • What are some elements on the periodic table you’re familiar with? • Why do you think the periodic table is organized the way it is???? • How do you think the elements vary or change throughout the periodic table?? • What do know about metals??? If you can, try listing some physical properties of metals
Periodic Table • In every chemistry room, you can expect to see a periodic table • The periodic table is made up of atomic symbols for each element • The atomic symbol for hydrogen is H, the atomic symbol for Carbon is C • The periodic table is listed in order of increasing atomic number • It is also arranged in vertical columns and horizontal rows
Periodic Table • Mendeleev, a Russian scientist, arranged the elements by atomic number in 1869 • He arranged it this way because of similarities in the chemical properties • For example, consider fluorine, chlorine, bromine, and Iodine • Because these elements have a similar electron arrangement, they react and behave in a very similar fashion
What is the Periodic Table? • A table that shows the names and atomic symbols of elements and is organized by increasing atomic number • Example: atomic symbol for the element Hydrogen is H
Groups 17 • Elements with similar chemical Properties that lie in the same vertical column are called groups • Groups are often referred to by the number over the column • Fluorine, Chlorine, Bromine and Iodine make up group 17
Groups vs. Periods Groupsare often referred to by the number over the column 1 17 18 There are 18 Groups in the periodic table 13 14 15 16 2 3 4 5 6 7 8 9 10 11 12
Groups vs. Periods The Periodic Table is also organized in horizontal rows called Periods 1 2 3 4 5 There are 7periods In the periodic table 6 7
What is the difference between Groups and Periods? Group • Groupsare vertical columns in the periodic table that contain elements with similar chemical properties; 18 groups exist • Periodsare horizontal rows in the periodic table, 7 periods exist Period
Alkali Metals • Group 1 Alkali metals are elements such as Lithium (Li), Sodium(Na), and Potassium (K) • These metals share similar chemical properties with each other • They are also very reactive and almost always combine and bond with other elements (Ex. NaCl) In group 1 we have The Alkali Metals
Alkaline Earth Metals • Group 2 Alkaline earth metals include elements such as Beryllium, Magnesium, and Calcium • These metals share similar chemical properties In group 2 we have the Alkaline Earth Metals
Halogens • Group 17 Halogens include elements such as Fluorine, Chlorine and Bromine • Many of these elements are gases or liquids at room temperatures • Once again, these elements have similar chemical properties In group 17 we have the Halogens
Noble Gases • Group 18 Noble Gases include elements such as Helium, Neon, and Argon • As their name implies, these elements are gases at room temperature • Noble gases do not react with other elements • For example, Helium is always pure helium atoms In group 18 we have the Noble Gases
Transition Metals • Transition metals include many of the elements we are familiar with such as Nickel, Iron, Copper, Gold and Silver In groups 3-12, we have the Transition Metals
What are the different types of groups? • Group 1 = Alkali Metals, Example: Sodium (Na), these metals are extremely reactive • Group 2 = Alkaline Earth Metals, Example: Magnesium (Mg) • Groups 3-12 =Transition Metals, Example: Iron (Fe) • Group 17 = Halogens, Example: Chlorine (Cl) • Group 18 = Noble Gases, Example: Argon (Ar), these gases are non-reactive or inert and exist in nature as single atoms
Metals, Semimetals, & Nonmetals • The periodic table is also classified into 3 basic different types of substances: -Metals -Semimetals -Nonmetals Semimetals Metals Nonmetals
Metals • Most of the periodic table is made up of metals • Metals Conduct Electricity • They are Malleable (hammered and flattened), Ductile (stretched and pulled into wires) and Lustrous (shiny)
What are Metals? • Most of the periodic table is made up of metals • Metals conduct electricity, they are malleable (can be flattened), ductile (can be stretched), and lustrous (shiny) • Ex: Iron (Fe) and Nickel (Ni) • Please draw:
Semimetals • The elements that divide the Metals and Nonmetals are semimetals • These elements are also called Metalloids • They have properties of both Metals and Nonmetals • Examples of Silicon (used in computers), and germanium and arsenic
What are Semimetals? • Diagonal band of Elements that separate metals and nonmetals and have properties of both metals and nonmetals • Ex: Silicon (Si) and Arsenic (As) • Please Draw:
Nonmetals • Nonmetals are just like they sound: elements that lack properties of metals • Nonmetals do not conduct electricity & they are brittle and dull in color • They also show much more variation than metals do • Examples would include the oxygen (gas), chlorine (gas), bromine (liquid), sulfur (solid), and carbon (solid)
What are Nonmetals? • Elements on the right side of the periodic table that do not have properties of metals • Nonmetals are brittle, do not conduct electricity, dull in color (not shiny) • Example: Sulfur (S), Carbon (C) • Please Draw:
Natural States of the Elements • Elements on the periodic table are different in how they behave and react with other elements • Some elements such as sodium are very reactive and readily bond with other elements • Other elements like gold, platinum and Helium are non-reactive or inert, and do not like to bond with other elements • It is these chemical properties that make metals like gold and platinum highly valuable and sought after
Noble Gases • If you remember, noble gases, such as helium, neon and argon are non-reactive and exist in nature as single atoms • We say these noble gases are monoatomic, or individual lone atoms that are not bonded to any other element • For example, consider a party balloon filled with Helium (He) • The balloon is filled with single, lone Helium atoms Helium Balloon = He
Diatomic Molecules • Some elements are found in their natural state as diatomic molecules • A diatomic molecule is a molecule made up of 2 atoms bonded together • For example consider a balloon filled with air • Air is a mixture of 79 % N2 gas and 20% O2gas and1% Argon gas • N2and O2 molecules exist in nature as diatomic molecules • Notice, Argon (Ar), is a monoatomic single atom Air Mixture = O2 = N2 = Ar
Other Diatomic Molecules at Room Temperature = Gases: H2 ,O2 , N2 , F2 & Cl2 = Liquids: Br2 = Solid: I2
What are the 7 naturally occurring diatomic molecules? • A molecule that exists as two atoms in its natural state • Examples are: H2 ,O2 , N2 , F2 , Cl2 , (Gases) Br2 (Liquid) and I2(Solid) = Gases: H2 ,O2 , N2 , F2 & Cl2 = Liquids: Br2 = Solid: I2
Summarize:(you can always write you own) • Compare and contrast Periods and Groups: • In which group can each of the following be found: • Transition metals • Halogens • Alkali Earth Metals • Noble Gases • Alkali Metals • Compare and contrast the reactivity of alkali metals and the noble gases; which group is more reactive? Which group is less reactive (inert)? • Explain the difference between diatomic molecules and monoatomic atoms: • How many diatomic molecules exist in nature? • Describe the physical properties for each of the following: • Nonmetals • Metals • Semimetals