Covalent Bonding & Lewis Structures

Slides:

Advertisements

Similar presentations

Chapter 9 Notes Mr Nelson 2009.

Advertisements

Part 1:Lewis Dot Diagrams and Structures

Covalent Bonding and Molecular Compounds.  Many chemical compounds are composed of molecules.  A molecule is a neutral group of atoms that are held.

Lewis Dot Accounting Ledger Method. Writing Lewis Dot Structures Determine total number of valence electrons in molecule. For cations (+) subtract electrons.

Cl Cl Br Br I I #7 Draw electron dot structures for each molecule

1 Drawing Lewis Structures A step-by-step guide See page 305.

Drawing Lewis Structures Hydrogens are always on the outside.

CHEM 5013 Applied Chemical Principles Chapter Seven Professor Bensley Alfred State College.

Covalent Bonds. Gases, liquids, or solids (made of molecules) Low melting and boiling points Poor electrical conductors in all phases Many soluble in.

Lewis Structure Practice. Ionic Lewis Structures Metal and Nonmetal First determine the chemical formula if it is not given to you. Draw the Lewis structure.

-Types of Covalent Bonds -Rules for Writing Lewis Dot Structures of Molecular Compounds Chemistry Mrs. Coyle.

Chemical Bonding © 2009, Prentice-Hall, Inc. Polar Covalent Bonds The greater the difference in electronegativity, the more polar is the bond.

Quick Review Covalent bond – two atoms held together by sharing electrons -- Usually occurs between nonmetals. Octet Rule – chemical compounds tend to.

Chapter 13 Lewis Structures.

© Prentice Hall 2001Chapter 11 Bonding Outer shell = valence electrons Octet rule - An atom is most stable if it has an outer shell of eight electrons.

1 Covalent bonding. 2 How does H 2 form? l The nuclei repel ++

LEWIS DOT STRUCTURES. MIT, Massachusetts, USA 1902.

A visual representation of covalent compounds.  1. Octet Rule ◦ Covalent compounds share electrons so that each atom has an octet of electrons (8) in.

Lewis Structures In Covalent Bonds valence electrons are distributed as shared or BOND PAIRS , and unshared or LONE PAIRS. • •• H Cl shared or bond pair.

Covalent Bonds.  Octet rule – all atoms want to have 8 electrons in their outer shell  Exception – helium (2)  Noble gases – very stable  Binary ionic.

Covalent Bonding Covalent bonding is the type of bonding that occurs between two non- metallic elements. Non-metallic elements do no form ions when they.

Objectives  I can draw simple Lewis structures of molecules.

Drawing Lewis Structures and predicting formulas of covalent compounds.

Chemistry 112 The Nature of Covalent Bonding. The Octet Rule in Covalent Bonding  In the case of covalent bonding, electrons are shared between atoms.

Bonding Unit Learning Goal #1: Analyze the relationship between the valence (outermost) electrons of an atom and the type of bond formed between atoms.

Covalent Bonds Forming single, double, and triple bonds.

COVALENT BONDING Chapter 6, Sections 1&2. Electronegativity  A measure of the ability of an atom in a chemical compound to attract electrons from another.

LEWIS STRUCTURES. How to draw Lewis structures for Neutral molecules 1. Determine the total valence electrons for the molecule. Find the # of valence.

1 Chapter 8 “Covalent Bonding” Ball-and-stick model.

Electron Dot Formulas Chemistry 7(C). Lesson Objectives Draw electron dot formulas – Ionic compounds – Covalent compounds Electron Dot Formulas.

1 Catalyst December 12, 2013 Summarize the properties of ionic compounds in complete sentences. Use page in the book if necessary.

Tuesday 10/19/10.  Return Naming Compounds Quiz  Collect Symbol Me Projects  Lewis structures  Metallic Bonding  Hydrogen Bonding  Jeopardy Review.

Covalent Bonding & Lewis Structures

Electron-Dot Model of Bonding: Lewis Structures Lewis structures are drawn by following simple rules. 1.Draw the molecular skeleton 2.Count the number.

Writing Lewis Dot Structures Determine the total number of valence electrons in molecule For cations (+) subtract electrons For anions (-) add electrons.

Lewis Structures and Molecular Geometry. Valence Electrons Electrons fill orbitals that are on the outside of the nucleus of the atom The number of electrons.

Chemical Bonding Molecular Polarity Vector Sum of Bond Polarities Why are some molecules polar but others are not?

Section 12.3 Lewis Structures 1.To learn to write Lewis structures 2.To learn to write Lewis structures for molecules with multiple bonds Objectives.

Lewis Structures Two Ways. 2 Drawing Lewis Structures 1) Count the total valence electrons for the molecule: To do this, find the number of valence electrons.

Unit 4 - Bonding Part 3 - Covalent Compounds. Molecules Covalent bond – a bond formed when atoms share one or more pairs of electrons Covalent bond –

Chemical bonds. Bonding, the way atoms are attracted to each other to form molecules, determines nearly all of the chemical properties we see. Chemical.

Nature of Covalent Bonding Part 1: Single Covalent Bonds.

University of Louisiana at Lafayette

Chemical Bonding Chemical Bonding

6.6 Lewis Structures for Molecules and Polyatomic Ions

Lewis Dot Structures Gilbert Lewis

HONC1234 Practice C3H8O2 C5H13N C4H10 C5H12O C8H19N

Chemical Bonding Three main types:.

Notes: Lewis Dot Structures Part 2

Chapter 8 – Lewis Structures of Covalent Molecules

Unit 5 – Lewis Structures of Covalent Molecules

Nature of Covalent Bonding

Lewis Structures.

Chapter 6-2 Lewis Structures (p. 206 – 207).

Covalent Bonds Covalent bond is a bond formed when 2 electrons are shared between atoms H + H forms H2 Lewis Structure of H2 Lewis Structure of F2 A lone.

Drawing Lewis Structures (electron dot diagrams)

Covalent Bonding.

Molecular Compounds.

Covalent Bonding & Lewis Structures

Chemical Bonding.

The Nature of Covalent Bonding

COVALENT BONDING.

Covalent Bonds 2a. Students know atoms combine to form molecules by sharing electrons to form covalent or metallic bonds or by exchanging electrons to.

3.1 Bonding. 3.1 Bonding Ionic Bonding • • • • • Cl Na • • • • • [ Na ]+ [ Cl ]- • • • • • • Form between a metal and a nonmetal Simplest expressed.

V. Lewis Dot Diagrams for Double & Triple Bonds + Polyatomic Ions

6.4 LEWIS STRUCTURE DIAGRAMS

7.6 – NOTES Lewis Structures

Valence Shell Electrons are all that matter in bonding.

7.4 – NOTES Lewis Structures

Presentation transcript:

Covalent Bonding & Lewis Structures Octet Rule: Atoms form bonds to obtain stable electron configurations… 8 e–’s in the outer shell like noble gases.

lone pair nonbonded pair unshared pair 1 shared pair 1 covalent bond single bond: 1 pair of shared electrons

How many unshared pairs (lone pairs)? structural formula: shows the arrangement of atoms How many unshared pairs (lone pairs)? 2

How many shared pairs? 3

N N O O Super Special Carbon C double bond: 2 pairs of shared e–’s triple bond: 3 pairs of shared e–’s N N Super Special Carbon C Carbon can form long chains because it forms up to 4 bonds on each C atom. This allows large biomolecules to form such as: proteins lipids (fats) carbohydrates (sugars/starches) nucleic acids (DNA/RNA)

Drawing Lewis Structures In 5 easy steps: PCl3 Count Connect Octet (if necessary)

Drawing Lewis Structures Count valence electrons of all atoms in the polyatomic ion or molecule. For anions (–), add e– ’s. For cations (+), subtract e– ’s. PCl3 5 + 3(7) = 26

Drawing Lewis Structures CONNECT atoms to the central atom with single bonds. Central atom is the least electronegative (never H) Keep track of the electrons: 26  6 = 20

Drawing Lewis Structures OCTET fill outer octets Keep track of the electrons: 26  6 = 20 20  18 = 2

Drawing Lewis Structures OCTET fill central octet Draw the Lewis structure for HCN Keep track of the electrons: 26  6 = 20 20  18 = 2 2  2 = 0

Drawing Lewis Structures If you run out of e–’s before the central atom has an octet… …form multiple bonds until it does. (by removing lone pairs from outer atoms, more than likely…)

Drawing Lewis Structures In 5 easy steps: Count (val e–’s) Connect (bonds) Octet (outer dots) Octet (central dots) (if necessary) form Multiple Bonds to fill central octet

O C O O C O Draw the Lewis structure for trichloromethane, CHCl3 Draw the Lewis structure for carbon dioxide, CO2 O C O O C O

large, long chain biomolecules. nucleic acids carbohydrates Quick Quiz! 1. Carbon atoms have 4 valence electrons to form up to 4 bonds. This allows carbon to form ______________ needed for life. large, long chain biomolecules. nucleic acids carbohydrates ALL of the above

Quick Quiz. 2. Which of the following diatomic molecules have a triple bond? (hint: draw the Lewis structures) O2 N2 Br2 H2 O O N N Br Br H H

Quick Quiz. 3. Draw the correct Lewis structure for dinitrogen monoxide , N2O. (aka: nitrous or laughing gas) hint: arrange the atoms as… N N O N N O