Memorize these element names & symbols:

Gases:

H hydrogen He helium Ne neon N nitrogen O oxygen F fluorine Cl chlorine Ar argon

Liquids:

Hg mercury Br bromine

Solids:

Li lithium B boron C carbon Na sodium Mg magnesiumAl aluminum Si silicon P phosphorusS sulfur K potassium Ca calciumCr chromium Mn manganese Fe ironCo cobalt Ni nickel Sn tinCu copper Zn zinc Pb leadAs arsenic I IodineSe selenium Ba bariumAg silver Au goldPt platinum U uranium

Arrangement of the Elements

Russian, Dmitri Mendeleev created The first “accepted” periodic table (1800’s)

1) Increasing atomic number

2) By groups or families:

columns

elements in a column have very similarproperties

3) periods

Rows (across)

Identify the element in:

Group 2A, period 4

Group 7A, period 5

Group 1 B, period 4

Ca

Cu

I

4) Metal, Nonmetal, Metalloid

Metals

metalloi

dsnonm

etal

s

Properties of Metals

high melting pt. (not Hg)

shiny

good conductors of heat & electricity

malleable & ductile

easily oxidized:lose e- in chem rxns

Properties of Nonmetals

low melting pt. (sol, liq, gas)

poor conductors

solids are brittle & dull

gain e- in chem rxns

Reduction (easily reduced))

xenon

carbon sulfur

Properties of Metalloids (either side of zig zag line)

Ex: B, Si, Ge, As, Sb

not Al

properties are intermediate between metal and nonmetal

silicon

used in semiconductorindustry (computer chips)

5) Electron Arrangement

Apartment building analogyatom

apartment building

nucleus ground floor

energy levels floors

sublevels

apartments

orbitals

rooms

electrons

people

types of orbitals

s spherical(one room

apt.)

p dumbell(3 room

apt.)

d

(5 room apt)

f (7 room apt)

PrincipalQuantumNumber (n)

energy level

number ofsublevels

type of sublevels

number oforbitals

max number electrons

1 1 1 1s 1 2

2 2 2 2s 2p 4 8

3 3 3 3s 3p 3d 9 18

4 4 4 4s 4p 4d 4f 16 32

n2 2n2

Electron Configuration:The “address” of the e-

Ex: 1s22s22p6

energy level sublevel

no. electrons

1s2

2s2 2p6

3s2 3p6 3d10

4s2 4p6 4d10 4f14

5s2 5p6 5d10 5f14

6s2 6p6 6d10 6f14

7s2 7p6 7d10 7f14

Energy level

sublevels

max. no. e-

sample electron configurations

H 1 e-

1s1

He 2e-

1s2

Li3e-

1s22s1

1s 2s

N7 e-

1s2

2s2 2p3

1s 2s 2p

Fe26e-

1s2 2s2 3s22p6 3p6 4s2 3d6

1s 2s 2p 3s 3p 4s

3d

Sample problem:

Given the electron configuration: 1s22s22p63s23p5

1. How many electrons are unpaired?1

2. How many electrons are in the outermost energy level ? 7

3s23p5

3. How many energy levels and sublevels are occupied? 3 energy levels (1, 2, 3)

5 sublevels (1s 2s 2p 3s 3p)

4. What element has this ground state configuration? Cl

Given the configuration:

1s22s22p63s23p64s23d104p31. How many electrons are in the outer energy

level?5, 4s24p3

2. How many electrons are unpaired?3

this is the config.of: As

Short method for e- config.

Use noble gases

1st 10 e-

[Ne]

1st 18 e- [Ar]

1st 36 e- [Kr]

1st 54 e- [Xe]

1st 86 e- [Rn]

Ex: Cl17 e-

[Ne]3s2 3p5

Ex: Ba56e-

[Xe]6s2

Ex: Zn30 e-

[Ar] 4s2 3d10

Si

14 e-

[Ne] 3s23p2

U92 e-

[Rn]

7s2 5f4

Pd

46 e-

[Kr] 5s2 4d6

using the periodic table to write electron configurations

s & p

period # (n)12

34

56

7

6

7

d period #(n) -1

f Period #(n) -2

1s2s3s

2p

3p4s 4p5s 5p6s 6p7s

3d

4d

5d

6d

4f

5f

Ex: Na [Ne]3s1 Ex: P [Ne]3s23p3

Ex: Co [Ar] 4s23d7 Ex: Sn [Kr]5s24d10 5p2

Ex: Pu [Rn]7s2 4f6

1. calcium [Ar] 4s2

2. chlorine [Ne] 3s2 3p5

3. cadmium[Kr] 5s2 4d10

Families of ElementsA

lkali

meta

lsA

lkalin

e e

art

h

meta

ls Transition

metals

Inner transition

metals

Nob

le

gases

halo

gen

s

Group 1A: Alkali metals

Li

Na

K

Rb

Cs

Fr

1s2

2s1

[Ne] 3s1[Ar] 4s1

All have 1

valence electron

outer energy level

Na

most reactive metals

always found combined in nature

react with water producing hydrogen gas

Group 2A: Alkaline Earth Metals

BeMgCa

Sr

Ba

Ra

1s2 2s2

[Ne]3s2

[Ar] 4s2

Mg

all have 2 valence electrons

quite reactive; always found combined w/ other elements in nature

Also react w/ water to produce

hydrogen gas

Group 7A: Halogens

F

Cl

Br

I

At

1s2 2s2 2p5

[Ne] 3s2 3p5 [Ar] 4s2 3d10 4p5

most reactive nonmetals

all have 7 valence e-

always found in compounds

form salts whencombined withmetals; ex: NaCl, KI

Cl

Group 8 A: Noble Gases

HeNeAr

Kr

Xe

Rn

1s2

1s2 2s2 2p6

[Ne] 3s2 3p6

most have 8 valence e-

Xe

chemically inert (unreactive);

don’t form compoundsfilled

outer levels makes them stable

Kr

Ar

Transition Metals

(B groups)

“typical” metals

unique property: form bright colored compounds

Au

Ag

Inner Transition elements

actinides serieslanthanide

series

Ac

La

many are synthetic (man made)

and radioactive

“yellow cake” uranium oxide

Trend: property that changes

Group

trend

change from top to bottom down a group

atomic radius, ionization energy, electronegativity

Periodic trend

Change from left to right across the row

I. Atomic Radius Indicates the size of an atom

Group trend

larger down the group

more energy levels makes the atoms larger

Li: 2 energy levels

K: 4 energy levels

Periodic trend

smaller acrossmore protons increases nuclear charge; pulls electrons in closer making the atom smaller

Li C Ne

+3

+6

+10arrange these atoms

from smallest to largest: Sr, Ne, Ca, S, Al

Ne S Al Ca Sr

III. Ionization Energy

Energy required to remove an e- from an atom

Group trenddecreases going

down

larger atoms hold their valence e- more loosely

Li

K

Periodic trend

Increases across; increase in nuclear charge (more p+) causeselectrons to be held more tightly

Na

+11

+13

Al Cl

+17

Ex: Which will lose an electron the easiest?

K or Ge ?

Mg or Ba ? Al or Cs ?

IV. Electronegativit

y

Number from 0-4 that indicates an atom’s attraction for e-

F 4.0

gains e- easily; very

reactive

Cs 0.7

loses e-

easily;very reactivegrou

p tren

ddecreases going down

Periodic trend

Increases going across (not noble gases

Ex: Arrange these atoms from greatest attraction for e- to least: P, Al, Sr, O O, P, Al, Sr

trends summarySmallest radius

Largest radius

Highest I.E.

Lowest I.E.

Highest EN (F)

Lowest EN