Covalent bonds can be depicted by straight lines.

Slides:

Advertisements

Similar presentations

1.7 Structural Formulas of Organic Molecules. Constitution The order in which the atoms of a molecule are connected is called its constitution or connectivity.

Advertisements

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

Intro to Bonding: Part 2: Covalent Compounds (Type 3 Binary Compounds)

Basic Concepts of Chemical Bonding Chapter 8. Three Types of Chemical Bonds Ionic bond Ionic bond –Transfer of electrons –Between metal and nonmetal ions.

Chemical Bonding I: The Covalent Bond

Simple Bonding Theory Review of Lewis Structures and VSEPR Theory.

Lewis Structures Chapter 8. Lewis Structures Lewis structures are representations of molecules showing all valence electrons, bonding and nonbonding.

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

Chemical bonding The name’s Bond…….chemical bond. Chemical.

Covalent Bonding Sec. 8.3: Molecular Structures. Objectives List the basic steps used in drawing Lewis structures. List the basic steps used in drawing.

Chemical Bonding and Molecular Structure Chapter 12 Sec Chapter 12 Sec

MOLECULAR GEOMETRY AND POLARITY

Representing Molecules. Bonding Chemical bonds are forces that cause a group of atoms to behave as a unit. Bonds result from the tendency of a system.

Polar bonds and molecular polarity Degrees between ionic and covalent.

Covalent Bonding Chemistry Mrs. Deiseroth. Electron-Dot Notation an electron-configuration notation in which only the valence electrons of an atom of.

1 Resonance and Formal Charge. 2 Resonance and Formal Charge: At the conclusion of our time together, you should be able to: 1. Define resonance 2. Determine.

October 6, 2015October 6, 2015October 6, 2015 GSCI 163 Spring 2010 material  Electron configuration  Bonding IonicIonic CovalentCovalent MetallicMetallic.

Section 12.3 Lewis Structures 1.To predict the electron arrangement in molecules 2.To learn to write simple Lewis structures 3.To learn to write Lewis.

Lewis Structures Of Covalent Compounds

Lewis Structures Of Covalent Compounds NAB Method.

John E. McMurry Paul D. Adams University of Arkansas Resonance Structures.

1 Resonance and Formal Charge. 2 SAMPLE PROBLEM:Writing Resonance Structures PLAN: SOLUTION: PROBLEM:Write resonance structures for the nitrate ion, NO.

Resonance Forms Resonance forms can be compared using the following criteria, beginning with the most important: 1.Has as many octets as possible. 2.Has.

Next Steps: Resonance. Formal Charge When atoms do not exhibit ‘normal’ bonding patterns, they will contain a ‘formal charge’. Formal Charge does not.

Writing Lewis Structures of Simple Covalent Molecules

Molecular Polarity Individual bonds tend to be polar, but that doesn’t mean that a molecule will be polar overall. To determine molecular polarity, you.

The Big Picture1 1.The importance of Coulombs Law: Atomic attraction Relative electronegativity Electron repulsion model for shapes of molecules Choice.

CH 9: Ionic and Covalent Bonding

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.

What happens when a molecule does not seem to have enough valence electrons?  Main goal is to satisfy octet rule for every atom in chemical compound.

Chapter 8 Allison Kim Eunwoo Kim Esther Park. Lewis Structure shows how valence electrons are arranged among the atoms in the molecules Only the valence.

What is polarity?  Focus on covalent bonds  Contributes to the properties of chemical compounds  Based on electronegativity difference between atoms.

Resonance Structures. Which one of these three structures is the correct one? As it turns out, laboratory measurements show that all three bonds are equal.

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

Covalent Bonds Multiple bonds!. Multiple Covalent Bonds Some elements can share more than one pair of electrons Double covalent bond: sharing 2 pair (4)

Resonance & Formal Charge Chapter 8 part 4. Resonance What if more than one valid Lewis dot structure is possible? Consider Nitrate ion. Nitrogen bound.

Boron tends to form compounds in which the boron atom has fewer than eight electrons around it (it does not have a complete octet). BH 3 = 6e –

Lewis Structures of Molecular Compounds, Resonance and Formal Charge

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

1 Resonance and Formal Charge. 2 Resonance and Formal Charge: At the conclusion of our time together, you should be able to: 1. Define resonance 2. Determine.

What you’ve learned so far…..  Atoms form bonds in more than one way  In IONIC bonding, atoms give up or gain electrons  In COVALENT bonding, atoms.

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.

Chapter 8: Lewis Structures and the Octet Rule AP Chemistry

The Scope of Organic Chemistry: An Overview Functional groups determine the reactivity of organic molecules Alkanes – No functional groups, only carbon.

Chapter 1 Lecture Introduction and Review Organic Chemistry, 8 th Edition L. G. Wade, Jr.

LEWIS DOT STRUCTURES Arrange the symbols such that the least electronegative element is in the center and the other elements are surrounding the.

Drawing Lewis Structures of Molecules Chapter 4 Section 4.

© 2009, Prentice-Hall, Inc. Covalent Bonding In covalent bonds atoms share electrons. There are several electrostatic interactions in these bonds: – Attractions.

1 Slater’s Rules for the Determination of Effective Nuclear Charge (Z*) 1) Write out the electronic configuration of the element and group the orbitals.

Bonding Chapter 8.

Lecture 7: Chemical bonding

Orbital Hybridization

Chapter 8 – Lewis Structures of Covalent Molecules

Chapter 6 Molecules and Covalent Compounds

Lewis Dot Structures Lewis Dot structures are used to represent the valence electrons of atoms in covalent molecules Dots are used to represent only the.

Octet Rule Objective: I will apply the octet rule to predict bonding in molecules and draw Lewis Dot Structures for molecules that contain double and.

Resonance & Formal Charge

Resonance Structures.

Drawing Lewis Structures (electron dot diagrams)

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

Delocalized Pi Bonding

Bonding Thermodynamics: why reactions occur Kinetics:

ionic charged covalent coordinate

7.6 – NOTES Lewis Structures

Valence Shell Electrons are all that matter in bonding.

10.5 (exceptions) Tro's Introductory Chemistry, Chapter 10.

7.4 – NOTES Lewis Structures

Resonance Structures.

Presentation transcript:

Covalent bonds can be depicted by straight lines. Bonding pairs of electrons are most often represented as straight lines: single bonds as a single line, double bonds as two parallel lines, and triple bonds as three parallel lines. Lone pairs of electrons are either shown as dots or are omitted. Structures of this type are called Kekulé structures.

Resonance Forms The carbonate ion has several correct Lewis structures. Three equivalent structures must be drawn to accurately represent the carbonate ion. The only difference between these structures is the placement of electrons.

But what is its true structure? The “true” structure can be thought of as the average of all three structures which is called a resonance hybrid. The 2 negative charges are delocalized over all three oxygen atoms.

Other examples of resonance:

Not all resonance forms are equal. Structures with a maximum of octets are most important. Charges should be preferentially located on atoms with compatible electronegativity. If this conflicts with rule 1, then rule 1 takes precedence. Structures with less separation of opposite charges are more important resonance contributors than those with more charge separation.

In some cases charge separation is necessary and guideline 1 takes precedence over guideline 2: If there are two or more charge separated resonance structures which comply with the octet rule, the most favorable one places the charges on atoms of compatible electronegativity: