Coloring the Periodic Table Families 9th Grade Science Mrs. Hennessey

Quick overview of Periodic Table    use 1st (9:00) Periodic Table (29:00, start at 19:00)  

Early Tries at Organizing Elements Up to the 1800’ s scientists were busy trying to discover new elements Not much thought was given to how they should be organized, so elements were just listed alphabetically. Some scientists thought the elements might be classified by color. Some thought by taste but then found that many were poisonous.

Because scientists liked to measure things, they were able to measure the atomic weight. ALONG COMES MENDELEEV He placed the name of an element on a piece of paper along with its known properties. Then he began to arrange the cards, keeping in mind that atomic mass and properties were very important. By 1871 he had all elements arranged and came up with a law.

MENDELEEV’S LAW If elements are arranged according to their atomic mass a pattern can be seen in which similar properties occur regularly.

Sometimes when arranging he would come to a place in which no element would fit. So he decided to leave it blank thinking that this might be a place for an element that had yet to be discovered. He could also predict the properties of the new element by looking at the properties of the known elements that were above and below the unknown element.

Families on the Periodic Table Elements on the periodic table can be grouped into families based on their chemical properties. Each family has a specific name to differentiate it from the other families in the periodic table. Elements in each family react differently with other elements. The elements in a group have the same number of electrons in their outer orbit. They tend to form ions by gaining or losing the same number of electrons

Important facts The periodic table arranges elements by: Arrangements of elements in order of increasing atomic number such that the elements show related chemical properties. The periodic table arranges elements by: -vertical columns called groups- group number tells the number of electrons in the outermost shell, (ie. the number of valence electrons). There are 18 groups. -horizontal rows called periods- period tells the number of shells or energy level. There are 7 periods.

ALKALI METALS Group 1 Hydrogen is not a member, it is a non-metal 1 electron in the outer shell Soft and silvery metals Extremely reactive, esp. with water because outer orbital shell has only one electron (unstable arrangement) Found in nature only as compounds Conduct electricity

HYDROGEN Hydrogen is a unique element. Like the alkali metals it has only one electron in its outer orbit. It has little else in common with the alkali metals: it is a colourless , odourless, tasteless highly flammable gas.

ALKALINE EARTH METALS Group 2 2 electrons in the outer shell White and malleable Reactive, but less than Alkali metals Conduct electricity

TRANSITION METALS Groups in the middle Good conductors of heat and electricity. Some are used for jewelry. The transition metals are able to put up to 32 electrons in their second to last shell. Can bond with many elements in a variety of shapes.

BORON FAMILY Group 3 3 electrons in the outer shell Most are metals Boron is a metalloid

CARBON FAMILY Group 4 4 electrons in the outer shell Contains metals, metalloids, and a non-metal Carbon (C)

NITROGEN FAMILY Group 5 5 electrons in the outer shell Can share electrons to form compounds Contains metals, metalloids, and non-metals

OXYGEN FAMILY Group 6 6 electrons in the outer shell Contains metals, metalloids, and non-metals Reactive

Halogens Group 7 7 electrons in the outer shell All are non-metals Most reactive Are often bonded with elements from Group 1

Noble Gases Con’t Group 8 Exist as gases Non-metals 8 electrons in the outer shell = Full Helium (He) has only 2 electrons in the outer shell = Full Not reactive with other elements,(inert) they almost never form chemical compounds with other elements Con’t

The lack of reactivity of noble gases is explained by their electronic structure. Their outer orbits are filled. They do not react with other atoms because they already have a stable arrangement of electrons.

The 3 Sections: Metals Non-Metals Metalloids Metals, Non-metals, and Metaloids ( the elements: chemistry lesson 25:00, stop at 19:00) Metals Non-Metals Metalloids

Characteristics of Metals - Metals are good conductor of heat and electricity. - Metals are shinny and ductile (stretchable) - Metals are malleable (can be pounded into thin sheets.) - A chemical property of metal is its reaction with water which results in corrosion.

Characteristics of Non-metals - Non-metals are poor conductors of heat and electricity. - Non-metals are not ductile or malleable. - Solid non-metals are brittle and break easily. - They are dull. - Many non-metals are gases.

Characteristics of Metalloids Are elements that possess both metallic and nonmetallic properties. Not strictly a group themselves, they are found on the right side of the periodic table, on both sides of the zigzag line that divides the metals and the nonmetals.

- Metalloids have properties of both metals and non-metals. - They are solids that can be shinny or dull. - They conduct heat and electricity better than non-metals but not as well as metals. - They are ductile and malleable.

Rare Earth Metals Some are Radioactive The rare earths are silver, silvery-white, or gray metals. Conduct electricity

Rows on the Periodic Table The groups of elements- the columns in the periodic table -have similar physical and chemical properties. These horizontal rows of elements are called periods. The first period contains two elements: hydrogen and helium. The second period contains eight elements, starting with lithium and ending with neon. As you go from left to right within a row, the atomic number increases and the elements gradually change from metallic to nonmetallic.

Atomic radius Atomic radius – size of an atom Increases down a group – more shells, electrons added further from nucleus

Ionic radius Increases down a group Decreases across a period Cations (positively-charged ions) Cations are smaller than their parent atom because the same number of protons in the nucleus pulls on less electrons. Metals commonly become cations. Anions (negative ions) Anions are larger than their parent atom because the same number of protons in the nucleus pulls on more electrons. Nonmetals commonly become anions.

Ionic Radius / Atomic Radius atomic radius is the radius of the atom when it's in neutral. ionic radius is the radius of the atom when it losses or gains electron ( become an ion) So, for the very same element the number of electrons in atom differs than the number of electrons of the ion which might cause a change in the number of orbitals and the radios.

Reactivity Non-metals Metals Period - reactivity decreases as you go from left to right across a period. Group - reactivity increases as you go down a group Why? The farther to the left and down the periodic chart you go, the easier it is for electrons to be given or taken away, resulting in higher reactivity. Non-metals Period - reactivity increases as you go from the left to the right across a period. Group - reactivity decreases as you go down the group. Why? The farther right and up you go on the periodic table, the higher the electronegativity, resulting in a more vigorous exchange of electron.

Video Periodic Table Formulas Lesson 1: Writing Formulas For Binary Ionic Compounds - YouTube 1st video Space Jam Space station tour

Periodic Table [1] First side of your sheet, color and label the groups. List two things you know about the groups. (10) Alkali Metals, Alkaline Earth Metals, Hydrogen, Transition metals, Boron, Carbon, Nitrogen, Oxygen, Halogen, Noble gases [2] Number the periods. List two things you know about the periods. [1] Second side of your sheet, neatly shade the areas of the table that contain metals, non-metals, and metalloids. [2] Label each. [3] List the characteristics of each on the sheet provided