Reminder…

From chapter 2 – The arrangement of “ground state” electrons in atoms ▪ Know the components of an electron configuration

o Principal energy level (“shell”) o Orbital - Orbital shapes and orientations o Number of electrons

▪ Know how to write an electron configurations ▪ Relate electron configurations to the Periodic Table ▪ Know how to write orbital “box” diagrams and how they

relate to orientations of orbitals

8A

1s7A6A5A4A3A

2B1B8B8B

1A

8B7B

2A

6B5B4B3B

1

2

3

4

5

6

7

1

2

3

4

5

6

7

6

7

Main group elements;s block (2 elements)

Transition elements;d block (10 elements)

Main group elements;p block (6 elements)

1s

Helium is also an s blockelement

3d

4d

5d

3p

4p

6d

2s

3s

4s

5s

6s

7s

2p

5p

6p

7p

4f

5f

Inner transition elements; f block

(14 elements)

4p

5p

▪ Be aware that atoms will either lose, gain or share electrons to form a chemical bond

Losing electrons results in a positive charge on an atom or group of atoms

Gaining electrons results in a negative charge on an atom or group of atoms

Sharing electrons results in no charge on the atom

cationcation

anionanion

▪ Know there are two main types of chemical bonds 1. Ionic: electrostatic bond between charged entities

called ions Positive ions: (single or multiple atoms) Negative ions: (single or multiple atoms)

2. Covalent: bond formed between two atoms by the sharing of their electrons

cationcationanionanion

Know the general approach to identify between formulas of covalent and ionic compounds o Covalent: All nonmetals o Ionic: Metal followed by nonmetals

Chapter 3 – Ionic & Covalent (molecular) Compounds

Learn how to identify and write the names of…

Ionic a. Made of charged species - Cation (+) & Anion (-)

i. Cation 1. Positively charged 2. Most are monatomic metals - one

exception is NH4+, a polyatomic

nonmetal ion ii. Anions

1. Negatively charged 2. Some are monatomic nonmetals and

some are polyatomic nonmetals b. Consist of one type of cation and one type of

anion c. Cations & Anions are bonded by an IONIC

BOND – electrostatic attraction d. Identified by - METALNONMETAL

Covalent (molecular) a. Made of neutral atoms b. Atoms are bonded by a COVALENT BOND – outer “shell”

electrons are shared between atoms c. Identified by all NONMETALS

i. Binary (two different types of atoms)

Monatomic Ions A single atom with a charge ▪ Monatomic cations are positively charged metal ions

Main group cations retain the name of the metal - Transition group cations retain the name of the

metal but may have a roman numeral following the name if multiple charge states exist

▪ Monatomic anions are negatively charged nonmetals the suffix “ide” is added to the name of the nonmetal

Know how to determine the charge of monatomic ions o Use the Periodic Table o Use basic math

Memorize these Charges on Ions in Groups 1A, 2A, 5A-7A

The charge varies for particular transition metal atoms, so roman numerals must be used. The charge can be determined by simple math.

Memorize common exceptions: Ag+, Zn2+, Cd2+, Ni2+, Al3+

The total number of positive charges must equal the total number of negative charges.

– AlCl3 is aluminum chloride

– LiBr is lithium bromide

– Ag2S is silver sulfide

– MgO is magnesium oxide– KCl is potassium chloride

Fe3+

Fe2+

Hg+

Hg2+

Cu2+

Cu+ Copper(I) ionCopper(II) ion

Iron(II) ionIron(III) ion

Mercury(I) ionMercury(II) ion

Cuprous ionCupric ion

Ferrous ionFerric ion

Mercurous ionMercuric ion

Cupr- from cuprum, the Latinname for copper

Hg from hydrargyrum, theLatin name for mercury

IonSystematic name

Common name

Origin of the symbol of theelement or the common name of the ion

Ferr- from ferrum, the Latinname for iron

Sn2+

Sn4+

Tin(II) ionTin(IV) ion

Stannous ionStannic ion

Sn from stannum, theLatin name for tin

For systematic names, use Roman numerals to show charge on the metal ion

– CuO is copper(II) oxide

– Cu2O is copper(I) oxide

– FeO is iron(II) oxide

– Fe2O3 is iron(III) oxide

Polyatomic ions Know that a polyatomic ion is two or more nonmetal atoms (a few exceptions) with a collective charge that is usually negative ▪ Know that each polyatomic ion has a distinct name –

Memorize, ammonium, acetate, hydroxide, nitrate, carbonate, bicarbonate, sulfate, phosphate

EOC

– NaNO3 is sodium nitrate.

– CaCO3 is calcium carbonate.

– NaH2PO4 is sodium dihydrogen phosphate.

– NH4OH is ammonium hydroxide.

– FeCO3 is iron(II) carbonate.

– Fe2(CO3)3 is iron(III) carbonate.

– CuSO4 is copper(II) sulfate.

– lithium ion and bromide ion form LiBr

– barium ion and iodide ion form BaI2

– aluminum ion and sulfide ion form Al2S3

– sodium ion and bicarbonate ion form NaHCO3

– potassium ion and phosphate ion form K3PO4

• Molecular compound:Molecular compound: a compound in which all bonds are covalent.

• Naming binary molecular compounds:– prefixes “di-”, tri-”, etc. are used to show the number of

atoms of each element; the prefix “mono-” is not used for the first atom, i.e. carbon monoxide

– NO is nitrogen monoxide (nitric oxide)

– SF2 is sulfur difluoride

– N2O is dinitrogen monoxide (laughing gas)

Naming one class of covalent compounds – Binary Covalent Know the rules for using prefixes

Naming one class of covalent compounds – Binary Covalent Know the rules for using prefixes

Prefixes for first atom Prefix Amount Di 2 Tri 3 Tetra 4 Penta 5 Hexa 6 Hepta 7 Octa 8 Nona 9 Deca 10

Prefixes for second atom Prefix Amount Mono 1 Di 2 Tri 3 Tetra 4 Penta 5 Hexa 6 Hepta 7 Octa 8 Nona 9 Deca 10

Know how to draw Lewis structures for covalent compound ▪ Know how to use the guidelines below OR Gino’s pieces

of common bonding approach

1. Determine the number of valence electrons in the molecule.

2. Determine the arrangement of atoms in the molecule.

3. Connect the atoms by single bonds.

4. Show bonding electrons as a single line; show nonbonding electrons as a pair of Lewis dots.

5. In a single bondsingle bond, atoms share one pair of electrons; in a double bonddouble bond, they share two pairs, and in a triple bondtriple bond they share three pairs.

Carbonic acidFormaldehydeAcetyleneEthylene

Hydrogen chlorideMethaneAmmoniaWater

H

H N H C H H ClH

HC C

HC C HH

HC

HHO

H

H2O (8) NH3 (8) CH4 (8) HCl (8)

C2H4 (12) C2H2 (10) CH2O (12) H2CO3 (24)

H

HHO

H

O OC HH

O

H-S-H O S O H-O-S-O-HO

OHydrogen sulfide Sulfuric acid

:: :::

Sulfur dioxide

8 electrons in the valence

shell of sulfur

10 electrons in the valence

shell of sulfur

12 electrons in the valence

shell of sulfur

• Examples– draw a Lewis structure for hydrogen peroxide,

H2O2.

– draw a Lewis structure for methanol, CH3OH.

– draw a Lewis structure for acetic acid, CH3COOH.

Bond Angle & Molecular Geometry Use Lewis Structures and the “green sheets” to: ▪ Predict the bond angle between the central and terminal

atoms ▪ Predict the electron pair and molecular geometries of a

molecule

The “green sheets”Links &

Lone PairsLinks &

Lone Pairs

Know how to predict individual bond polarity A covalent bond is polar if there’s an unequal sharing of electron “fuzz”. Use an electronegativity table… Polar if there is more than 0.4 difference between their electronegativity values.

Know how to predict overall molecular polarity ▪ Predict if a molecule is polar – an unequal sharing of

electron “fuzz”. Molecule is polar if… There are lone pair electrons around the central atom OR The terminal atoms are different than each other

H-P-H

H

P

ClCl Cl

Cl ClH-O-P-O-H

O-H

O

Phosphorus pentachloride Phosphoric acidPhosphine

8 electrons inthe valence shell of P

10 electrons inthe valence shell of P

10 electrons inthe valence shell of P

H-S-H O S O H-O-S-O-HO

OHydrogen sulfide Sulfuric acid

:: :::

Sulfur dioxide

8 electrons in the valence

shell of sulfur

10 electrons in the valence

shell of sulfur

12 electrons in the valence

shell of sulfur

Draw Lewis Structure & Predict Polarity

:

Carbonic acidFormaldehydeAcetyleneEthylene

Hydrogen chlorideMethaneAmmoniaWater

H

H N H C H H ClH

HC C

HC C HH

HC

HHO

H

H2O (8) NH3 (8) CH4 (8) HCl (8)

C2H4 (12) C2H2 (10) CH2O (12) H2CO3 (24)

H

HHO

H

O OC HH

O

Draw Lewis Structure & Predict Polarity