WednesdayNovember 7, 2012

(Pop Quiz – Ionic Bonds, Octet Rule, Lewis Structures,

Salts, and Acids; WS - Covalent Bonding)

Bell RingerWednesday, 11-7-12

Identify the following acids as either binary or

oxyacids, then name them.

MgCl2

HCl

H3PO4

KBrbinary acid

oxyacid

Name these salts, then determine the acid and base from which the salts were formed.

potassium bromide

magnesium chloride

hydrochloric acid

phosphoric acid

HBr and KOH

HCl and Mg(OH)2

Announcements

Happy November

Assignment Currently Open

Summative or Formative? Date Issued Date Due Date Into

GradeSpeed Final Day

QUIZ 9 S6 10/26 10/26 11/16

WS – Properties of Ionic and Covalent

CompoundsF11 11/1 11/9 11/9

QUIZ 10 S7 11/2 11/2 11/16

WS – Ionic Bonds, The Octet Rule, and

Lewis StructuresF12 11/5 11/9 11/9

Pop QuizIonic Bonds, Octet Rule, Lewis

Structures, Salts, and AcidsYou may use the following reference materials

on this Pop Quiz:• your Periodic Table

•your Electronegativity/Bonding Character Chart• the Worksheet titled “Properties of Ionic and

Covalent Compounds”• the Worksheet titled “Ionic Bonds, The Octet

Rule, and Lewis Structures”

Covalent BondingIt’s

nice to share!

Covalent Bondingand Molecular Compounds

A molecule is a neutral group of atoms that are

held together by covalent bonds.

A molecule may consist of two or more atoms of

the same element, or two or more different

types of atoms.A molecular compound is a chemical compound

whose simplest units are molecules.

A chemical formula indicates the relative numbers of atoms

of each kind in a chemical compound by using atomic

symbols and numerical subscripts.

A molecular formula shows the types and numbers of atoms

combined in a single molecule of a molecular compound.A diatomic molecule is a

molecule containing only two atoms.

Covalent Bondingand Molecular Compounds

H2O NaCl

CO2

O2

Formation of a Covalent BondAs atoms approach each other, their charged particles begin to interact.

Nuclei and clouds attract each other - potential energy decreases.

The two nuclei and the two e- clouds repel each other

– potential energy increases.

At a given distance, the repulsion equals the attraction, energy

potential is at its lowest, and the bond forms.

Characteristics of a Covalent BondBond length is the distance between two bonded atoms at their minimum potential energy, that is, the average distance between two bonded atoms.

Example) The bond length of H-H is 75 pm.At this length, the one electron of each atom is

shared by both atoms.

Characteristics of a Covalent BondBond energy is the energy required to

break a chemical bond and form neutral, isolated atoms.

Example) The bond energy to break H2 is 436 kJ.

Sharing electrons allows each atom to experience the effect of the stable electron

configuration of a Noble Gas.Keep in mind that bond lengths and bond energies vary with the types of atoms that

have bonded.

Bond Length and Bond Energy

Multiple Covalent BondsA covalent bond produced by

the sharing of two pairs of electrons between two atoms is

called a double bond.

Multiple Covalent BondsA covalent bond produced by the sharing of three pairs of

electrons between two atoms is called a triple bond.

Multiple Covalent BondsDouble and triple bonds

are referred to as multiple bonds.

Multiple Covalent BondsSample Problem

Draw the Lewis structure of methanal (formaldehyde)

CH2O

WorksheetCovalent Bonding