CHAPTER 12: Periodic Table

1. CHAPTER 12: Periodic Table

2. Early 1860’s • Scientists knew some of the properties of more than 60 elements that existed. • BUT…..they were not in any order.

3. Demitri Mendeleev 1869 • Mendeleev was the first scientist to write the ________and ________ of each element on the an index card. • He used properties such as; _______, __________, and _______________. • He then arranged the elements in order of _______________________. • Mendeleev discovered a ________ __________that took place among the elements going from left to right across and up and down.

4. Demitri Mendeleev 1869 • Periodic – means happening at _______ ________, “___________”. • Example – the days of the week. • He left _______ or question marks for ________ or ______________ elements. • Mendeleev’s arrangement of elements became known as the ___________ ________ ___ _______________.

5. Henry Moseley 1914 • Moseley – a British scientist, determined the ________ ________ (# of protons) in an atom. • _________ _______ is also arranged by _________ ________ ________ or by increasing number of protons. • __________ _____– the _________ ________and __________ properties of elements change periodically with the element’s atomic numbers.

6. Periodic Table • A periodic table is an arrangement of ___________ in columns, based on a set of ___________ that repeat from row to row. (page 338-339)

7. Periods are the ___________ in the periodic table (horizontal). • Elements change from metals to ___________ as you move from leftto rightacross the period. • Groups/Families are the ________ on the periodic table. (vertical) • Properties of elements repeat in a predictable way. (Periodic Law) Group -- Period ------------

8. Classes of elements • Elements are classified as metals, metalloids, and nonmetals based on their ____________. • Metals – Start at the far ________ hand side and stop at the zigzag line. • - Most elements are __________. • - Most are _______ at room temperature. • - The exception: Mercury (Hg) • - Metals tend to be shiny, luster. • - Malleable – hammered into thin sheets. • - Good conductors of electricity/heat. • - Ductile – made into thin wires.

9. Classes of elements • Nonmetals – Start at the far _______ hand side and stop at the zigzag line. • - More than half are _______ at room temperature. • - Nonmetals tend to be dull, lack luster. • - Brittle –will shatter if struck with a hard object. • - Poor conductors of electricity/heat - insulator • - Non-ductile – cannot be drawn into wires.

10. Classes of elements • Metalloids– elements that _________ the zigzag line. • - Tend to have ____________ that are in between metals and nonmetals. • - Called ____________________ Tellurium is shiny, but it is brittle and can easily be smashed into a powder. Boron is very brittle. At high temperatures it is a good conductor of electricity/heat.

11. Valence Electrons • A Valence Electron is an electron that is in the highest occupied ________ ________ of an atom. • Elements in a ________ have similar properties because they have the same number of valence electrons.

12. Alkali Metals family • Group 1 • Most reactive metals • Reactivity increases from the top to the bottom. • Francium is the most reactive metal! • So reactive many are kept under oil to prevent reacting with water or oxygen. • Found in nature only in a compound. • _______ Valence Electron • Give away one valence electron and form _______ in order to become stable.

13. Alkaline Earth Metals Family • Group 2 • ___ Valence Electrons • Give away ___ valence electrons and form +2 Ions in order to become stable. • Less ______ than group 1. • Magnesium used in photosynthesis. • Calcium used in teeth and bone.

14. Transition Metals • Groups 3 – 12 • 1 or 2 valence electrons • ______ _______ than alkaline earth metals • Shiny, good conductors of heat and electricity. • Their ________ vary widely. Iron is very reactive and can react with oxygen in the air to form rust. Many are solids at room temp, except Mercury. Many are silver in color except Gold. Titanium not very reactive.

15. Transition Metals Lanthanides and Actinides • Transition metals from periods 6 and 7. • Lanthanides are shiny reactive ______________. • - Some of these elements are used to make steel. • Actinides are radioactive, or _________. • - Elements listed after Plutonium, element 94 do not occur naturally in nature.

16. Boron Family • Group 13 • ____ Valence electrons • Give away 3 valence electrons and form _______ in order to become stable. • 1 metalloid (Boron) • Five metals • Aluminum is the most abundant metal in the Earth’s crust.

17. Carbon Family • Group 14 • 4 Valence Electrons • Can _______ ________ ____ or take 4 valence electrons and form +/- 4 Ions in order to become stable. • 1 Nonmetal • 2 Metalloids • 3 Metals • With the exception of water, most of the compounds in your body contain carbon.

18. Nitrogen Family • Group 15 • ___ Valence Electrons • Take 3 valence electrons and form -3 Ions in order to become stable. • 2 nonmetals • 2 metalloids • 2 Metals • Nitrogen and Phosphorus are used in fertilizers.

19. Oxygen Family • Group 16 • ___ Valence Electrons • Take 2 valence electrons and forms -2 Ions in order to become stable. • 3 nonmetals • 1 metalloid • 2 metal • Oxygen is the most abundant element in the Earth’s Crust.

20. Halogen Family • Group 17 • ____ Valence electrons • Take 1 valence electron and form -1 Ions in order to become stable. • Most _________ nonmetals • Reactivity increases from bottom to top. • Fluorine is the most reactive nonmetal.

21. Noble Gas Family • Group 18 • ___ Valence Electrons • Un-reactive (Do not form Ions) because they are _______. • The Noble Gases are _______ and ___________. • Used in light bulbs (Argon). • Make balloons float (Helium). • Used to make neon lights.