Do Now

1. Do Now • Write the electron configuration for Scandium. • Draw the electron configuration for Scandium. • How many sig figs does 0.0032 have? • How many sig figs does 1.0000 have? 1s22s22p63s23p64s23d1 2 5

2. The Periodic TABLE of ELEMENTS

3. QUICK REVIEW • What do the group numbers (of the A elements) indicate on the periodic table? • What do the periods indicate in the periodic table? Number of Valence Electrons Number of Energy Levels

4. V.I.V. • Atomic Radius – One-half the distance between the nuclei of two like atoms in a diatomic molecule. Very Important Vocabulary

5. Atomic Radius • Indicates its relative size • Increases as you move down a group in the periodic table. • Decreases as you go across a period (Number of energy levels stay the same). The radius of an atom is governed by: the number of layers of electrons around the nucleus the pull the outer electrons feel from the nucleus.

6. Show What You Know • How would we explain why the atomic radius of a phosphorus atom is smaller than the atomic radius of a magnesium atom? • How would we explain why the atomic radius of a sodium atom is smaller than the atomic radius of a cesium atom?

7. Show What You Know Some Mo’ • As you move across a period (row) of elements From left to right, the atomic radii of atoms (size of atoms) tends to __________________. Draw and Label an arrow at the top of the periodic table representing this trend. • As you move down a group of elements, the atomic radii of atoms tends to ______________________. Draw and Label an arrow at the side of the periodic table representing this trend. DECREASE INCREASE

8. V.I.V • Ionization Energy – Energy required to overcome the attraction of the nuclear charge and remove an electron from an atom. • 1st Ionization Energy – Energy required to remove the 1st loosely held, outermost electron.

9. Ionization Energy • Once the electron is removed the atom becomes ionized. • Generally decreases as you down a group • Generally increases as you across a period. If the ionization energy is high, that means it takes a lot of energy to remove the outermost electron. If the ionization energy is low, that means it takes only a small amount of energy to remove the outermost electron. http://intro.chem.okstate.edu/1314f00/lecture/chapter7/lec111300.html

10. Show What You Know • As you move across a period (row) of elements From left to right, the Ionization energy of atoms (size of atoms) tends to __________________. Draw and Label an arrow at the top of the periodic table representing this trend. • As you move down a group of elements, the Ionization energy of atoms tends to ______________________. Draw and Label an arrow at the side of the periodic table representing this trend. INCREASE DECREASE

11. Show What You Know Some Mo’ For each of the following sets of atoms, decide which has the highest to lowest ionization energies and why. a.  Mg, Si, S b.  Mg, Ca, Ba c.  F, Cl, Br d.  Ba, Cu, Ne e.  Si, P, N S  Si  Mg Mg  Ca  Ba F  Cl  Br Ne  Cu  Ba N  P  Si

12. V.I.V • Electronegativity – The tendency of an atom to attract electrons when they are chemically combined. Uses the Pauling electronegativity which ranges from 0.0 to 4.0. Ex: Cesium – 0.7 Flourine – 4.0

13. Electronegativity • Increases as you go across periods • Decreases as you go down groups • Cesium as the lowest electronegativity • Flourine has the highest electronegativty • Noble gases do not have a Pauling rating because they do not readily bond to other atoms.

14. Show What You Know • As you move across a period (row) of elements From left to right, the ELECTRONEGATIVITY of atoms (size of atoms) tends to __________________. Draw and Label an arrow at the top of the periodic table representing this trend. • As you move up a group of elements, the ELECTRONEGATIVITY of atoms tends to ______________________. Draw and Label an arrow at the side of the periodic table representing this trend. INCREASE INCREASE

15. Show What You Know Some Mo’ • An atom of which of the following elements has the greatest ability to attract electrons?A. silicon B. sulfur C. nitrogen D. chlorine Choose which element has the highest electronegativity? Li, Na, Rb K, Si, Cl F, Cl, Br Ne, Ar, Kr

16. Quick Check • Sodium Calcium Tungsten Aluminum Fluorine Barium Argon • Which has the largest atomic radius? • Whish has the smallest atomic radius? • Which has the greatest ionization energy? • Which has the greatest electronegativity?

17. Extended Periodic Table

18. Standard Periodic Table

19. HYDROGEN • Does not match the properties of any other group so it stands alone. • It is placed above group 1 but it is not part of that group. • It is a very reactive, colorless, odorless gas at room temperature. • Color Hydrogen PINK

20. Metals and Nonmetals (V.I.V) DRAW A HEAVY BLACK LINE BETWEEN THE METALS AND NONMETALS • Metals • High electrical conductivity • High luster • Ductile (Can be made into wire) • Malleable (Can be beaten into thin sheets) • All are solids at room temp (Except for mercury) • 80% of all elements are metals (Approx) • NonMetals • Poor conductors of electricity • Nonlustrous • Some are gases at room temp (Oxygen, Chlorine) • Some are brittle solids (Sulfur)

21. V.I.V • Metalloids • Borders the line that separates the metals from the nonmetals • Have properties of metals and nonmetals • Silicon and Germanium are used in the manufacturing of computer chips and solar cells.

22. V.I.V • Alkali Metals • Group 1- 1 valence electron • Electron configuration ends in “s” • Very reactive metals • Do not occur freely in nature • Softer than other metals • Explodes when exposed to water (Including moisture in skin) • Stored in oil to keep them from reacting with Oxygen and moisture in the air. • Color the Akali Metals PURPLE VIDEOTIME

23. V.I.V • Alkaline Metals • Group 2 – 2 Valence electrons • Electron configuration ends in “s” • Very reactive metals (But not as reactive as Alkali metals) • Do not occur freely in nature • Harder than alkali • Barium is the most reactive • Ca reacts with cold water (slow reaction) Be and Mg reacts with hot water or steam. • Color the Alkaline Earth Metals RED

24. V.I.V • Transition Metals • Shiny, good conductors of heat • Electron configuration ends in “d” • Moderate range of reactivity • Wide range of properties • 1 or 2 valence electrons and they are present in more than one energy level • Can hold more electrons in there energy levels • Low ionization energy • Color the Transition Metals GREEN.

25. V.I.V • Halogens • The term halogen means “salt-former” • Nonmetal • Group 17 – 7 valence electrons • Readily bonds with metals • Do not exist in an uncombined state • Free halogens are very reactive • Electron configuration ends in “p” • Color the Halogen Group BLUE

26. V.I.V • Noble Gases (Also Known As Inert Gases) • Do not readily form compounds • Fairly nonreactive • Complete outer shells • Very low electronegativities • Electron configuration ends in “p” • High ionization energy • Color the Noble Gases YELLOW

27. V.I.V • Inner Transition Metals – They were taken out and placed at the bottom so the table wouldn’t be so wide • Lathanides • Are often called rare-earth metals but are not rare • Silvery, shiny metals with high melting points • Reactive • Chemical properties are very similar • Used for tinting sunglasses and making high-quality camera lenses • Electron configuration ends in “f” • Color the LathanidesORANGE

28. Inner Transition Metals Continued • Actinides • Radioactive and unstable • Chemical properties are similar • Electron configuration ends in “f” • Combines directly with most nonmetals • Color the Actinides LIGHT BLUE

29. More Periodic Table Notes • All elements 1 – 92 occur in nature, EXCEPT for technetium (Tc, 43) and promethium (Pr, 61). • Elements with atomic numbers greater than 92 are called transuranium. • These elements are synthesized in particle acclerators in very small amounts.