Chapter 6 PERIODIC TABLE

How does Electron Configuration relate to the Periodic Table? 2 10 6 14 1 3 4 5 7 2 3 4

Do Now Which statement is true? (use Periodic Table) Elements in the same column ↕ has same # of outer shell electrons Elements in the same row ↔ has same # of outer shell electrons

Dmitri mendeleev (1869) Arrangement: Interesting observations: produced the first periodic table for the known 63 elements Arrangement: Increasing atomic mass kept similar elements in a column left blanks for unknown elements Interesting observations: Mendeleev predicted the properties of the missing elements.

Mendeleev’s pt

Henry moseley (1914) Arrangement: Increasing atomic number Interesting observations: Discrepancies in Mendeleev’s table disappeared (Te before I)

Parts of periodic table Vertical Column Row Group Period Family

Same # of occupied energy levels

Groups or families Same # of electrons in their outer orbital Share similar chemical properties

Properties of Metals, Non-metals, & Metalloids Conducts heat & electricity Ductile Malleable Luster Solid at room temp. (except Hg) Forms cations (+) Non-Metal: Brittle S/l/g at room temp. Forms anions (-) Metalloids Semi-conductors Properties of nonmetals and metals

Metals, non-metals, & metalloids Note: Most elements are _________ metals

Tour of the Periodic Table Main-group elements Also called representative elements (s- and p-blocks) E- config: regular & consistent Group: same # of val. e-

Tour of the Periodic Table Inner Transition Metals

Alkali Metal (Group 1, except H) Hydrogen Most common element in universe charge: 1+ or 1- Alkali Metal (Group 1, except H) Highly reactive with water Soft and can be easily cut Charge:1+ Alkaline-earth metal (Group 2) Less reactive than alkali metals Harder than alkali metals Charge: 2+

Transition metals (d-block) No identical valence electrons (charge varies) Less reactive than group 1 & 2 Inner Transition metals (f-block) Nuclei are unstable – radioactive (charge varies)

Halogens (Group 17) Most reactive group of non-metals Likes to react with alkalis to produce salts charge :1-

Noble gases (Group 18) Low chemical reactivity b/c very stable Outermost energy level is full Does not form ions Glow brightly when an electric discharge is passed through them

Do now: Copy names into pg-2 Inner Transition Metals

Alkali Metals: Na loses 1 e- Formation of ions Octet rule: atoms are most stable when they have 8 val. e- CATION: (+) ions Alkali Metals: Na loses 1 e- 1s22s22p63s1 1s22s22p6 (Na) (Na+) Ne E- config Bohr Diagram

ANION: (-) ions Halogens: Cl gains 1 e- 1s22s22p63s23p5 1s22s22p63s23p6 (Cl) (Cl-) Ar

As you look down a column, the outermost principle energy level __________________. (but the number of valence e-‘s stays the same) As more and more levels become filled with electrons, the nucleus becomes ______________ effective at attracting the outer electron(s). This is known as the “shielding effect.” (As you look down a column, even though the nucleus theoretically is stronger since it has more protons, it is NOT effective at holding onto the outer electrons.) Which energy level has NO shielding? ____________ Which atom holds onto the outer electron tighter, K or Rb? Why? ____ has one more filled level than ____ and therefore is _____ effective at holding onto the outermost (valence) electron. INCREASES LESS 1 Rb K LESS Pg-7

Is the shielding effect an issue with a row?_____ Row, Period , Series Val. n=2 n=2 n=2 n=2 n=2 n=2 n=2 n=2 energy level   filled ____ ____ ____ ___ ___ ____ ___ ____ Levels The energy level is not changing. What is changing? Is the nucleus getting stronger?_________. Is it effective?________ In a row, ___________ ___________(and not shielding) determines the trend. NO 2 b/c noble gas 1 1 1 1 1 1 1 # of electron & protons YES YES NUCLEAR CHARGE Pg-8

Recap: Column: the __________ _________ dictates the trends Recap: Column: the __________ _________ dictates the trends. Row: the increasing strength of the __________ dictates the trends. ELECTRON SHIELDING NUCLEUS

Atomic Radius (pg-9) Distance from nucleus to outer electrons Bond radius = ½ distance between nuclei of adjacent atoms.

Atomic Radius Down a Group: Increases Reason: more energy levels more shielding Across a Period: Decreases More nuclear charge (+) pulls outer most e- closer to nucleus

Ionic radii (pg-9) positive lose smaller gain negative larger Metals tend to _________ electrons and become ____________ions. (gain or lose) positive or negative) ** (metal ions are ___________than metal atoms) (smaller or larger) Non- metals tend to _______ electrons and become __________ ions. (gain or lose) (positive or negative) ** (non-metal ions are ______________than non-metal atoms) (smaller or larger) smaller gain negative larger

Ionization Energy (IE) – pg10 Energy required to remove an electron from an atom or ion (form (+) ion).

Ionization Energy (IE) Down a Group: Decreases (easier to remove an electron) Reason: 1. more energy levels (outermost electrons are farther from nucleus) 2. more shielding (less attraction btw p+ & val. e-) Across a Period: Increases (harder to remove an electron) 1. more nuclear charge, p+ ↑ 2. radius decreases Electron-shielding remains the same

Circle the correction answer & answer the last 2 questions Ionization Energy pg-10 Circle the correction answer & answer the last 2 questions Lower down in a column the atoms are larger / smaller and have more attractiveness / shielding so it is easier to remove an e- from the outer shell. It is harder/easier to remove an electron from a small atom with no shielding. It gets harder/easier to remove that electron as you move to the right as it approaches a perfect octet. Which column would be very difficult to go in and remove and electron from? Noble gases So the column with the highest Ionization Energy = Group # 18, Noble gases

IE Which element has the least IE? the most?

#3 Electronegativity (pg-11) the attraction of an atom to a pair of electrons in a bond **EXCEPT NOBLE GASES Fluorine has the highest value of “4.0”

Electronegativity (EN) Down a Group: Decreases (less attraction towards bonding e-) Reason: 1. more energy levels 2. more shielding Across a Period: Increases (more attraction towards bonding e-) 1. radius decreases (val. e- closer to nucleus) 2. nuclear charge increases, p+ ↑

Which column does NOT bond with any element (because it has a perfect Fluorine atom pulls harder on the shared pair of electrons. They are shared “unevenly” Electronegativity of Fluorine is > , = , < the electronegativity of hydrogen Chlorine atoms share the pair of electrons “evenly” Electronegativity of Chlorine is > , = , < the electronegativity of Chlorine In water, does Hydrogen or Oxygen pull harder on the shared pair of electrons? ____________ Which column does NOT bond with any element (because it has a perfect octet)? ____________________ (No electronegativity values are assigned) NOBLE GASES

MOLECULE/MOLE/MASS CONVERSIONS FOR DIATOMIC ELEMENTS Atomic mass: mass in grams = 1 mole of that element Example: 12 g C = 1 mol C Molecular mass: mass of a molecule = 1 mole of that molecule Example: 32 g O2 = 1 mol O2 Diatomic Elements (BrINClHOF): Br2 I2 N2 Cl2 H2 O2 F2 Elements found in pairs