Chem Ch 6-7 Review

valence e-

outermost electrons→ form chemical bonds

metallic bonds

between metals

metallic bonds: info.

e- between the metals form a “SEA”/ FREELY MOVING E-

metallic bonds: valence e-

delocalized/ HIGH CONDUCTIVITY

metals are….

malleable & ductile

ionic bonds

between CATION & ANION

ionic bonds: info

E- are TRANSFERRED

ionic bonds: cations & anions

POSITIVE VALUES of CATIONS MUST BE EQUAL to the NEGATIVE VALUE of ANIONS

ionic bond: attraction

POTENTIAL ENERGY = ELECTROSTATIC POTENTIAL ENERGY (Eel)

ionic bond: formula

Ee1= 2.31E-19J x nm(q1 x q2/ d)

Ee1

energy (j)

2.31E-19J x nm

CONSTANT (K)

q1

+

q2

-

d

total distance (nm)

as ions APPROACH EACH OTHER

Eel= DECREASES

ELECTROSTATIC ATTRACTIONS = INCREASE

energy minimum

corresponds to FORMATION & MAXIMUM STABILITY/ BOND LENGTH

ions are pushed too close together

electrostatic potential energy =  INCREASES

BOND = LESS STABLE

lattice energy (U)

ions COMBINE to FORM A CYRSTALLINE SOLID

crystal lattice of NaCl

BONDS = STRONGER / ELECTROSTATIC POTENTIAL ENERGY = MORE NEGATIVE

net effect

DECREASE IN Eel→ STRONGER IONIC BOND

conceptually of Eel= k( q1 x q2/d)

CHARGE= LARGEST CHARGE → MOST NEGATIVE

conceptually of Eel= k(q1 x q2/d) part 2

DISTANCE= SHORTEST DISTANCE → MORE NEGATIVE

concept of Eel= k(q1 x q2/d) * if SAME DISTANCE

CHARGE TAKES PRIORITY

TRENDS: IONIZATION & ELECTRONEGATIVITY

INCREASE - LEFT TO RIGHT

DECREASE- DOWN THE GROUP

TRENDS: RADI

DECREASE- LEFT TO RIGHT

INCREASE- DOWN THE GROUP

crystal lattice: pressure on ions

SHIFT IN ALIGNMENT W SIMILAR IONS→ REPEL

covalent bonds

SHARE E-

covalent bonds: PE of 2 H

2 atoms APPROACH the PROTON is ATTRACTED to the E- (VICE VERSA)

COVALENT bonds: MINIMUM

BOND FORMATION

covalent bonds are…

MOLECULES

DIATOMIC MOLECULES

BOND THEMSELVES

DIATOMIC MOLECULES EXAMPLES

H2, N2, F2, O2, Cl2, BR2

POLYATOMIC IONS

COMBINE W IONS OF OPPOSITE CHARGE= IONIC BOND

POLYATOMIC BONDS ARE

COVALENTLY BONDED MOLECULES= ION

POLYATOMIC BONDS EXAMPLE

NH4+ (COVALENT) + OH- (COVALENT)→ NH4OH (IONIC)

AMMONIUM FORMULA

NH4

AMMONIUM CHARGE

-1

HYDROXIDE FORMULA

CH

HYDROXIDE CHARGE

-1

ACETATE FORMULA

C2H3O2

ACETATE CHARGE

-1

CARBONATE FORMULA

CO3

CARBONATE CHARGE

-2

HYDROGEN CARBONATE/BICARBONATE FORMULA

HCO3

HYDROGEN CARBONATE/ BICARBONATE CHARGE

-1

NITRITE FORMULA

NO2

NITRITE CHARGE

-1

NITRATE FORMULA

NO3

NITRATE CHARGE

-1

CHROMATE FORMULA

CrO4

CHROMATE CHARGE

-2

DICHROMATE FORMULA

Cr2O7

DICHROMATE CHARGE

-2

PHOSPHATE

PO4

PHOSPHATE CHARGE

-3

HYDROGEN PHOSPHATE FORMULA

HPO4

HYDROGEN PHOSPHATE CHARGE

-2

DIHYDROGEN PHOSPHATE FORMULA

H2PO4

DIHYDROGEN PHOSPHATE CHARGE

-1

HYPOCHLORITE FORMULA

CIO

HYPOCHLORITE CHARGE

-1

CHLORITE FORMULA

ClO2

CHLORITE CHARGE

-1

CHLORATE FORMULA

CiO3

CHLORATE CHARGE

-1

PERCHLORATE FORMULA

CiO4

PERCHLORATE CHARGE

-1

PERMANGATE FORMULA

MnO4

PERMANGATE CHARGE

-1

SULFITE FORMULA

SO3

SULFITE CHARGE

-2

HYDROGEN SULFITE/ BISULFITE FORMULA

HSO3

HYDROGEN SULFITE CHARGE

-1

SULFATE FORMULA

SO4

SULFATE CHARGE

-2

HYDROGEN SULFATE/ BISULFATE

HSO4

HYDROGEN SULFATE

-1

CYANIDE FORMULA

CN

CYANIDE CHARGE

-1

PEROXIDE FORMULA

O2

PEROXIDE CHARGE

-2

ionic or covalent: ionic

ionic bond- >2.0

ionic or covalent: covalent

covalent bond- < or = 2.0

IONIC OR COVALENT? REMEMBER

largest En goes first

EN- Hydrogen

2.1

EN- Boron

2.0

EN- Carbon

2.5

EN- Nitrogen

3.0

EN- Oxygen

3.5

EN: Fluorine

4.0

EN- Chlorine

3.0

EN- Sulfur

2.5

EN- Phosphorous

2.1

EN- Bromine

2.8

EN- Iodine

2.5

polar covalent bonding: polar covalent

unequal sharing of e-

polar covalent bonding: non-polar covalent

equal sharing of e-

EN: pure covalent

=0

carbon-hydrogen

non-polar