Sigma and Pi Bonding SWBAT: Draw Quantum Mechanical models of molecules using sigma and pi bonding.

Slides:



Advertisements
Similar presentations
1 1.5The Nature of Chemical Bonds: Valence Bond Theory Covalent bond forms when two atoms approach each other closely so that a singly occupied orbital.
Advertisements

1. What determines the state of matter a molecule is at room temperature? What determines the ability of a molecule to develop cohesive and adhesive forces?
1 Covalent Bonding: Orbitals Chapter The four bonds around C are of equal length and Energy.
Hybridization Section Introduction A hybrid results from combining 2 of the same type of object and it has characteristics of both Atomic orbitals.
Chapter 9 Covalent Bonding: Orbitals Hybridization The mixing of atomic orbitals to form special orbitals for bonding. The atoms are responding as needed.
COVALENT BONDING: ORBITALS Chapter 9. Hybridization The mixing of atomic orbitals to form special molecular orbitals for bonding. The atoms are responding.
Covalent Bonding: Orbitals.
Valence Bond Theory. How do bonds form? The valence bond model or atomic orbital model was developed by Linus Pauling in order to explain how atoms come.
© Prentice Hall 2001Chapter 11 Atomic Orbitals We cannot know the exact course of electrons as they orbit the nucleus - Heisenberg uncertainty principle.
Bonding - HL Orbital overlap, hybridization and resonance.
Delocalization of Electrons Section Introduction Delocalization allows the pi electrons to spread over more than two nuclei This spreading out of.
Chapter 10 Chemical Bonding II
IONIC & COVALENT BONDING ZUMDAHL CH 2 HS-PS1-_____.
V-B theory can’t explain some observations about
Hybridization of Atomic Orbitals Some Material Copyright PGCC CHM 101 Sinex Some Graphics from Nelson Chemistry 12 Textbook.
Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Covalent Bonding: Hybrid Atomic Orbitals.
Hybrid Orbitals. Why Covalent Bonds Exist Atoms share electrons when their orbitals overlap When orbitals overlap, electrons are simultaneously attracted.
Bonding theory Two methods of approximation are used to describe bonding between atoms. Valence bond method Bonds are assumed to be formed by overlap of.
Hybrid Orbitals With hybrid orbitals the orbital diagram for beryllium would look like this. The sp orbitals are higher in energy than the 1s orbital but.
SWBAT: Draw sp hybrid bonding orbitals for carbon
Lecture 2 Chemical Bonds: Atomic Orbital Theory and Molecular Orbital Theory Dr. A.K.M. Shafiqul Islam
CHEMICAL BONDING. 1.Introduction 2.Octet rule 3.Different types of bonding 4.Valency Bond Theory Topics Covered.
Hybridization Section Introduction A hybrid results from combining 2 of the same type of object and it has characteristics of both Atomic orbitals.
Hybridization of Atomic Orbitals PGCC CHM 101 Sinex.
1 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Valence Bond Theory Orbital shapes, Individual (“isolated”) Atoms.
Hybrid Orbitals. Sigma Bond (σ) Covalent bond which the electron density is concentrated symmetrically along the internuclear axis Line joining the two.
Hybridization and Other Good Stuff. Introduction A hybrid results from combining two of the same type of objects, and it has characteristics of both Atomic.
Hybridization Combination of atomic orbitals to form hybrid orbitals OR Hybridization is also way to explain molecular shapes that can't be explained easily.
To offer more in-depth explanations of chemical bonding more sophisticated concepts and theories are required 14.1 and 14.2 Hybridization 1.
4.6 Quantum Mechanics and Bonding Hybridization We need next to examine the relationship between: isolated atoms (with valence e’s in s,p, and d orbitals.
Warm-up  Draw the following in VSEPR a) Butane b) Cyclopropane c) Dichloromethane d) 2-Bromopropane.
Structure and Properties of Organic Molecules
Hybridization.
Chapter 8 “Covalent Bonding” Part 3 Ball-and-stick model.
COVALENT BONDING: ORBITALS Chapter 9. Hybridization The mixing of atomic orbitals to form special molecular orbitals for bonding. The atoms are responding.
Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Chemistry FIFTH EDITION by Steven S. Zumdahl University of Illinois.
Tuesday, March 22 nd Take out your notes.
Chapters 8 , 9 & 22: Covalent Bonding and Naming Compounds
Sigma and Pi bonding and Molecular Orbital Theory.
Lecture 2 Chemical Bonds: Atomic Orbital Theory and Molecular Orbital Theory Dr. A.K.M. Shafiqul Islam
Part 1: Molecular Orbitals
Orbital Hybridization
18.2 Bonding in Methane and Orbital Hybridization
Overlap and Bonding We think of covalent bonds forming through the sharing of electrons by adjacent atoms. In such an approach this can only occur when.
Molecular Orbitals and Hybridisation
CHAPTER 8: ADVANCED THEORIES OF COVALENT BONDING
SUPA Chemistry Sigma and Pi Bonds.
Unsaturated Carbon Hybridization and Pi Bonding
Chapter 2: Structure and Properties of Organic Molecules
Rules for Predicting Molecular Geometry   1.  Sketch the Lewis structure of the molecule or ion 2.  Count the electron pairs and arrange them in.
Part 1: Molecular Orbitals
Hybridization of Orbitals
HYBRIDIZATION SIGMA AND PI BONDS
Honors Chemistry Mrs. Coyle
Chemistry 141 Monday, November 20, 2017 Lecture 32 Hybridization
COVALENT BONDING: ORBITALS
Bonding Theories.
Notice the numbers on the diagram.
Finishing off Hybridization
Qantum Mechanics and Bonding Hybridization
Hybrid Orbitals Consider beryllium:
Covalent bonds are formed by:
Qantum Mechanics and Bonding Hybridization
Molecular Shapes.
Covalent Bonding: Orbitals What role do orbitals play in bonding?
DEPARTMENT OF CHEMISTRY
POSTULATES Condition for bond formation Strength of the bond
Valence Bond Theory (VBT) Molecular Orbital Theory (MOT)
9.6 Multiple Bonds Honors 2019.
Presentation transcript:

Sigma and Pi Bonding SWBAT: Draw Quantum Mechanical models of molecules using sigma and pi bonding

Number of hybrid orbitals formed Number of atoms bonded to the C Carbon Hybridization Type of hybrid Atomic orbitals used Number of hybrid orbitals formed Number of atoms bonded to the C Aufbau Chart sp3 s, p, p, p 4 sp2 s, p, p 3 sp s, p 2

Number of hybrid orbitals formed Number of atoms bonded to the C Carbon Hybridization Type of hybrid Atomic orbitals used Number of hybrid orbitals formed Number of atoms bonded to the C Aufbau Chart sp3 s, p, p, p 4 sp2 s, p, p 3 sp s, p 2

sp3 Hybridization

Number of hybrid orbitals formed Number of atoms bonded to the C Carbon Hybridization Type of hybrid Atomic orbitals used Number of hybrid orbitals formed Number of atoms bonded to the C Aufbau Chart sp3 s, p, p, p 4 sp2 s, p, p 3 sp s, p 2

sp2 Hybridization C2H4

Number of hybrid orbitals formed Number of atoms bonded to the C Carbon Hybridization Type of hybrid Atomic orbitals used Number of hybrid orbitals formed Number of atoms bonded to the C Aufbau Chart sp3 s, p, p, p 4 sp2 s, p, p 3 sp s, p 2

sp Hybridization C2H2

Covalent Bonds The formation of a covalent bond involves the overlapping of half filled atomic orbitals The two different categories of covalent bonds are Sigma and Pi covalent bonds

Sigma bonding Bond is formed by the axial overlapping of half filled atomic orbitals The electron cloud formed is cylindrically symmetrical about inter nuclear axis The electrons constituting sigma bonds are called sigma electrons

3 Types of Sigma Bonding s-s overlap s-p overlap p-p overlap

sp-overlaps Example: CH4

Strength of Sigma Bonds The strength of three types of sigma bonds varies as follows p-p > p-s > s-s A p-p overlap is greater than an s-s overlap allowing it to be stronger

Pi Bonding This type of covalent bond is formed by the lateral or sidewise overlap of the atomic orbitals The orbital overlap takes place in a way that their axes are parallel to each other but perpendicular to the internuclear axis The pi bond consists of two charge clouds above and below the plane of the atoms involved in the bond formation The electrons involved in the p bond formation are called pi electrons

Pi Bonding

Sigma and Pi Bonding Sigma bonds are stronger than pi bonds (greater overlap between orbitals occurs) Pi bonding between the two atoms is formed only in addition to a sigma bond (Sigma first then Pi) Atoms rotate around sigma bonds but not pi bonds The shape of the molecule is controlled by the orientations of sigma bonds around the central atom. Pi bonds are superimposed on sigma bonds.

Sigma and Pi bonding with Oxygen (O2) 1s22s22p4 s orbitals are filled and the 2px orbital is filled The 2py and 2pz orbitals are partially filled An O=O molecule has one sigma and one pi bond (connect both lobes of a p orbital for a pi bond…. Draw two lines for one pi bond)

Oxygen (O2) Nitrogen (N2)

Carbon Hybridization Review http://www.chemit.co.uk/resource/download/94