SECTION II: BUILDING MODELS
|
|
- Julian Townsend
- 5 years ago
- Views:
Transcription
1
2 SECTION II: BUILDING MODELS Lesson 9 New Smells, New Ideas Lesson 10 Two s Company Lesson 11 Let s Build It Lesson 12 What Shape Is That Smell? Lesson 13 Sorting It Out Lesson 14 How Does the Nose Know?
3 LEARNING OBJECTIVES Apply VSEPR to predict electronic geometry and shapes of simple molecules Distinguish between polar and nonpolar bonds in molecules Predict polarity of simple molecules from bond polarity and molecular shape
4 LESSON 9: NEW SMELLS, NEW IDEAS Ball-and-Stick Models A ball-and-stick model is a three-dimensional representation of a molecule that shows us how the atoms are arranged in space in relationship to one another.
5 TOTAL NUMBER OF GROUPS DICTATES ELECTRONIC GEOMETRY Octet rule: Two linear Three trigonal planar Four tetrahedral Additional possibilities (expand octet): Five trigonal bipyramidal Six - octahedral
6 Electronic geometry considers bonded atoms only. Molecular geometry considers unbonded pairs as well
7 LESSON 10: TWO S COMPANY Electron Domains
8 YOU WILL BE ABLE TO: determine the shapes of small molecules explain how lone pairs of electrons influence molecular shape describe electron domain theory and how it relates to molecular shape
9 KEY QUESTION How do electrons affect the shape of a molecule?
10 MOLECULAR GEOMETRY Molecular geometry is the three-dimensional arrangement of a molecule s atoms in space. Linear Bent Trigonal-planar Tetrahedral Trigonalpyramidal Trigonal-bipyramidal Octahedral
11 Electron domain: The space occupied by valence electrons in a molecule, either a bonded pair(s) or a lone pair. Electron domains affect the overall shape of a molecule. Electron domain theory: The idea that every electron domain in a molecule is as far as possible from every other electron domain in that molecule.
12 VALENCE SHELL ELECTRON PAIR REPULSION THEORY
13 Molecular Shape VSEPR theory assumes that the shape of a molecule is determined by the repulsion of electron pairs. VSEPR theory states that repulsion between the sets of valence-level electrons surrounding an atom causes these sets to be oriented as far apart as possible.
14 VSEPR THEORY VSEPR (pronounced vesper ) stands for Valence Shell Electron Pair Repulsion Based on Electron Dot (Lewis structures) Theory predicts shapes of compounds based on electron pairs repelling (in bonds or by themselves) Electrons around central nucleus repel each other. So, structures have atoms maximally spread out
15 METHANE AS A MODEL Examine a simple hydrocarbon such as methane. Methane s chemical formula: CH 4 What do you predict for it s molecular structure? What do you predict for it s geometric shape? (remember VSEPR) 15
16 The overall geometric shape of a methane model is tetrahedral. The H atoms are at the vertices of a tetrahedron. Bonded pairs of electrons take up space. This space is called an electron domain Incorrect models electron pairs are not equally distant. Correct models All angles between bonds are the same.
17 Tetrahedral shape: The shape around an atom with four bonded pairs of electrons. This is the shape of a methane molecule.
18 ANOTHER EXAMPLE Now examine another simple molecule such as ammonia. Ammonia s chemical formula: NH 3 An electron domain describes the area occupied by a set of electrons in a bond or a lone pair. What do you predict for it s molecular structure? What do you predict for it s geometric shape? 18
19 Unshared electron pairs repel other electron pairs more strongly than bonding pairs do. This is why the bond angles in ammonia and water are somewhat less than the o bond angles of a perfectly tetrahedral molecule.
20 Trigonal pyramidal one atom at the apex and three atoms at the corners of a trigonal base, resembling a tetrahedron, However, the three hydrogen atoms are repelled by the electron lone pair in a way that the geometry is distorted to a trigonal pyramid. 20
21 Use VSEPR theory to predict the molecular geometry of boron trichloride, BCl 3. First write the Lewis structure. Boron is in Group 13 and has 3 valence electrons. Chlorine is in Group 17 so each chlorine atom has 7 valence electrons. The three B-Cl bonds stay farthest apart by pointing to the corners of an equilateral triangle, giving 120 o angles between the bonds. This would be trigonal-planar geometry.
22 The z plane 3-D
23 Each shape has a name (you will have to memorize these) tetrahedral trigonal pyramidal bent linear trigonal planar
24 Note: that lone pairs of electrons effect the shape but are ignored in the name of the geometry
25 The geometry of a molecule refers to the positions of atoms only. 25
26 VSEPR AND MOLECULAR GEOMETRY
27 VSEPR AND MOLECULAR GEOMETRY
28 methane, CH 4 Tetrahedral Bonds are all evenly spaced apart
29 .. ammonia NH 3 Trigonal Pyramidal Less repulsion between the bonding pairs of electrons surprise: the lone pairs occupy more space than the bonded atoms (with very few exceptions)
30 H O H.. water H 2 O bent Two unbonded pairs of electrons make bond angles slightly less than tetrahedral due to greater repulsion
31 .. Carbon dioxide CO 2 linear Bonded electrons can take maximum position apart 180
32 .. Barium floride BF 3 Trigonal planar No lone pairs of electrons allows maximum bond angle in 1-D plane
33 LESSON 11: LET S BUILD IT Molecular Shape
34
35 CHEMCATALYST 1. What is the Lewis dot structure of formaldehyde, CH 2 O? 2. Draw formaldehyde s structural formula. 3. How many electron domains do you think this molecule has? Explain your reasoning.
36 KEY QUESTION How can you predict the shape of a molecule?
37 YOU WILL BE ABLE TO: predict and explain molecular shape, including in molecules with multiple bonds
38 PREPARE FOR THE ACTIVITY Work in groups of four. Using the gumdrop, marshmallow, and toothpick kits, build a model of formaldehyde, CH 2 O.
39 DISCUSSION NOTES Double or triple bonding changes the number of electron domains around an atom, affecting the overall shape of a molecule. Trigonal planar shape: A flat triangular shape found in small molecules with three electron domains surrounding the central atom.
40 DISCUSSION NOTES (CONT.) Linear shape: A geometric shape found in small molecules with two electron domains surrounding the central atom. The number of electron domains is more important in determining the structure of a molecule than is the number of atoms.
41 DISCUSSION NOTES (CONT.) The more atoms in a molecule, the more combinations of shapes you might see together.
42 WRAP UP How can you predict the shape of a molecule? Drawing the Lewis dot structure of a molecule allows us to predict its three dimensional shape. The presence of double or triple bonds changes the number of electron domains around an atom, which in turn affects the overall shape of the molecule. The shape of large molecules is determined by the smaller shapes around individual atoms.
43 Water, H 2 O, has two unshared pairs, and its molecular geometry takes the shape of a bent or angular molecule. Bent
44 Molecule Lewis Structure Number of electron pairs SHAPE CH 4 4 Tetrahedral NH 3 4 Trigonal Pyramidal (3 shared 1 lone pair)
45 Molecule Lewis Structure Number of electron pairs SHAPE H 2 O 4 (2 shared 2 lone pairs) Bent or V CO 2 2 Linear
46 Molecule Lewis Structure Number of electron pairs SHAPE BeCl 2 2 Linear BF 3 3 Trigonal Planar
47 LESSON 14: HOW DOES THE NOSE KNOW? Receptor Site Theory
48 CHEMCATALYST 1. Suppose you needed to separate coins but could not see them. Explain how you would make a machine that detects and sorts coins. 2. How do you think your nose detects a smell?
49 KEY QUESTION How does the nose detect and identify different smells?
50 YOU WILL BE ABLE TO: come up with a plausible model to explain how smell works in the nose, based on the evidence thus far describe the receptor site model
51 PREPARE FOR THE ACTIVITY Work in groups of four.
52 DISCUSSION NOTES Scientists have proposed many theories about how smell works and created models corresponding to these theories.
53 DISCUSSION NOTES (CONT.) Receptor site theory: The currently accepted model explaining how smells are detected in the nose. Molecules fit into receptor sites that correspond to the overall shape of the molecule. This stimulates a response in the body.
54 WRAP UP How does the nose detect and identify different smells? The currently accepted model for smell describes smell molecules landing in receptor sites that fit the shape of the smell molecules. In the receptor site model, each receptor site has a specific shape that corresponds to the shape of just a few smell molecules.
55 CHECK-IN One of the molecules that gives coffee its smell is 2- furylmethanethiol. 1. Write down everything you know about how this molecule is detected by the nose. 2. Draw a possible receptor site for this molecule.
56 MOLECULAR POLARITY AND DIPOLE-DIPOLE FORCES The strongest intermolecular forces exist between polar molecules. Polar molecules act as tiny dipoles. A dipole is created by equal but opposite charges that are separated by a short distance. The direction of a dipole is from the dipole s positive pole to its negative pole. A dipole is represented by an arrow with its head pointing toward the negative pole and a crossed tail at the positive pole. The dipole created by a hydrogen chloride molecule is represented below: H Cl
57 The forces of attraction between polar molecules are known as dipoledipole forces. The negative region in one polar molecule attracts the positive region in adjacent molecules. So the molecules all attract each other from opposite sides.
58 Which atom attracts e- more? electronegativities H Cl δ + δ H H C = O O = C = O
Living By Chemistry. Unit 2: SMELLS Molecular Structure and Properties
Living By Chemistry Unit 2: SMELLS Molecular Structure and Properties Section II: Building Models Lesson 9 New Smells, New Ideas Lesson 10 Two s Company Lesson 11 Let s Build It Lesson 12 What Shape Is
More informationChapter 6. Preview. Objectives. Molecular Compounds
Section 2 Covalent Bonding and Molecular Compounds Preview Objectives Molecular Compounds Formation of a Covalent Bond Characteristics of the Covalent Bond The Octet Rule Electron-Dot Notation Lewis Structures
More informationVSEPR. Valence Shell Electron Pair Repulsion Theory
VSEPR Valence Shell Electron Pair Repulsion Theory Vocabulary: domain = any electron pair or bond (single, double or triple) is considered one domain. bonding pair = shared pair = any electron pair that
More informationName: Period: Date: What Is VSEPR? Now explore the Compare Two Structures link. Try changing the display to explore different combinations.
Name: Period: Date: What Is VSEPR? Exploring The Valence Shell Electron Pair Repulsion (VSEPR) model. Go to the Purdue University website to explore VSEPR theory. http://www.chem.purdue.edu/gchelp/vsepr/structur2.html
More informationIntroduction to VSEPR Theory 1
1 Class 8: Introduction to VSEPR Theory Sec 10.2 VSEPR Theory: The Five Basic Shapes Two Electron Groups: Linear Geometry Three Electron Groups: Trigonal Planar Geometry Four Electron Groups: Tetrahedral
More informationIntroduction to Chemical Bonding
Chemical Bonding Introduction to Chemical Bonding Chemical bond! is a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together Why are most
More informationChemical Bonding. Section 1 Introduction to Chemical Bonding. Section 2 Covalent Bonding and Molecular Compounds
Chemical Bonding Table of Contents Section 1 Introduction to Chemical Bonding Section 2 Covalent Bonding and Molecular Compounds Section 3 Ionic Bonding and Ionic Compounds Section 4 Metallic Bonding Section
More informationChapter 13: Phenomena
Chapter 13: Phenomena Phenomena: Scientists measured the bond angles of some common molecules. In the pictures below each line represents a bond that contains 2 electrons. If multiple lines are drawn together
More informationChapter 6. Preview. Lesson Starter Objectives Chemical Bond
Preview Lesson Starter Objectives Chemical Bond Section 1 Introduction to Chemical Bonding Lesson Starter Imagine getting onto a crowded elevator. As people squeeze into the confined space, they come in
More informationChapter 6. Preview. Lesson Starter Objectives Chemical Bond
Preview Lesson Starter Objectives Chemical Bond Section 1 Introduction to Chemical Bonding Lesson Starter Imagine getting onto a crowded elevator. As people squeeze into the confined space, they come in
More informationLewis structures show the number and type of bonds between atoms in a molecule or polyatomic ion.
VSEPR & Geometry Lewis structures show the number and type of bonds between atoms in a molecule or polyatomic ion. Lewis structures are not intended to show the 3-dimensional structure (i.e. shape or geometry)
More informationChemical Bonding and Molecular Models
25 Chemical Bonding and Molecular Models A chemical bond is a force that holds groups of two or more atoms together and makes them function as a unit. Bonding involves only the valence (outer shell) electrons
More informationMolecular Geometry. Valence Shell Electron Pair. What Determines the Shape of a Molecule? Repulsion Theory (VSEPR) Localized Electron Model
Molecular Geometry Learn Shapes you will Because the physical and chemical properties of compounds are tied to their structures, the importance of molecular geometry can not be overstated. Localized Electron
More informationLewis Theory of Shapes and Polarities of Molecules
Lewis Theory of Shapes and Polarities of Molecules Sulfanilamide Lewis Structures and the Real 3D-Shape of Molecules Molecular Shape or Geometry The way in which atoms of a molecule are arranged in space
More informationMolecular shapes. Balls and sticks
Molecular shapes Balls and sticks Learning objectives Apply VSEPR to predict electronic geometry and shapes of simple molecules Determine molecule shape from electronic geometry Distinguish between polar
More informationChapter 9 Molecular Geometry. Lewis Theory-VSEPR Valence Bond Theory Molecular Orbital Theory
Chapter 9 Molecular Geometry Lewis Theory-VSEPR Valence Bond Theory Molecular Orbital Theory Sulfanilamide Lewis Structures and the Real 3D-Shape of Molecules Lewis Theory of Molecular Shape and Polarity
More informationAt the end of this lesson, students should be able to :
At the end of this lesson, students should be able to : (a) Explain Valence Shell Electron Pair Repulsion theory (VSEPR) (b) Draw the basic molecular shapes: linear, planar, tetrahedral, and octahedral.
More informationSKILL-BUILDING EXERCISE
4. O and H Solution 1. Carbon has an electronegativity of 2.5, while the value for hydrogen is 2.1. The difference is 0.3, which is rather small. The C H bond is therefore considered nonpolar. 2. Both
More information8.3 Bonding Theories > Chapter 8 Covalent Bonding. 8.3 Bonding Theories. 8.1 Molecular Compounds 8.2 The Nature of Covalent Bonding
Chapter 8 Covalent Bonding 8.1 Molecular Compounds 8.2 The Nature of Covalent Bonding 8.3 Bonding Theories 8.4 Polar Bonds and Molecules 1 Copyright Pearson Education, Inc., or its affiliates. All Rights
More information4 Copyright Pearson Education, Inc., or its affiliates. All Rights Reserved.
CHEMISTRY & YOU Chapter 8 Covalent Bonding 8.1 Molecular Compounds 8.2 The Nature of Covalent Bonding 8.3 Bonding Theories 8.4 Polar Bonds and Molecules 1 Copyright Pearson Education, Inc., or its affiliates.
More informationof its physical and chemical properties.
8.4 Molecular Shapes VSEPR Model The shape of a molecule determines many of its physical and chemical properties. Molecular l geometry (shape) can be determined with the Valence Shell Electron Pair Repulsion
More informationMolecular Geometry and Bonding Theories. Molecular Shapes. Molecular Shapes. Chapter 9 Part 2 November 16 th, 2004
Molecular Geometry and Bonding Theories Chapter 9 Part 2 November 16 th, 2004 8 Molecular Shapes When considering the geometry about the central atom, we consider all electrons (lone pairs and bonding
More informationMolecular Geometry & Polarity
Molecular Geometry & Polarity Learn Shapes you will Because the physical and chemical properties of compounds are tied to their structures, the importance of molecular geometry can not be overstated. Localized
More informationCovalent Bonding. In nature, only the noble gas elements exist as uncombined atoms. All other elements need to lose or gain electrons
In nature, only the noble gas elements exist as uncombined atoms. They are monatomic - consist of single atoms. All other elements need to lose or gain electrons To form ionic compounds Some elements share
More informationLewis Dot Structures for Methane, CH 4 The central C atom is bonded by single bonds (-) to 4 individual H atoms
Chapter 10 (Hill/Petrucci/McCreary/Perry Bonding Theory and Molecular Structure This chapter deals with two additional approaches chemists use to describe chemical bonding: valence-shell electron pair
More informationChem 1075 Chapter 12 Chemical Bonding Lecture Outline. Chemical Bond Concept
Chem 1075 Chapter 12 Chemical Bonding Lecture Outline Slide 2 Chemical Bond Concept Recall that an atom has and electrons. Core electrons are found to the nucleus. Valence electrons are found in the s
More informationCovalent Bonding. In nature, only the noble gas elements exist as uncombined atoms. All other elements need to lose or gain electrons
In nature, only the noble gas elements exist as uncombined atoms. They are monatomic - consist of single atoms. All other elements need to lose or gain electrons To form ionic compounds Some elements share
More information4/25/2017. VSEPR Theory. Two Electron Groups. Shapes of Molecules. Two Electron Groups with Double Bonds. Three Electron Groups.
Chapter 10 Lecture Chapter 10 Bonding and Properties of Solids and Liquids 10.3 Shapes of Molecules and Ions (VSEPR Theory) Learning Goal Predict the three-dimensional structure of a molecule or a polyatomic
More informationShapes of Molecules and Hybridization
Shapes of Molecules and Hybridization A. Molecular Geometry Lewis structures provide us with the number and types of bonds around a central atom, as well as any NB electron pairs. They do not tell us the
More informationMolecular Geometry. Objectives N H H. The objectives of this laboratory are to:
Objectives The objectives of this laboratory are to: Molecular Geometry Write Lewis structure representations of the bonding and valence electrons in molecules. Use the VSEPR model to predict the molecular
More informationChapter 12 Structures and Characteristics of Bonds Objectives
Objectives 1. To learn about ionic and covalent bonds and explain how they are formed - what holds compounds together? 2. To learn about the polar covalent bond are all covalent bonds equal? 3. To understand
More information1. Which of the following is an example of a structural formula?
1. Which of the following is an example of a structural formula? A. B. C. D. 2. According to the VSEPR Theory, which of the following molecules will have a linear geometry? A. B. C. D. 3. Which type of
More informationThe shape of simple molecules (and parts of larger molecules) can be easily predicted using the VSEPR model
1 PREDICTING MOLECULAR SHAPE The shape of simple molecules (and parts of larger molecules) can be easily predicted using the VSEPR model VSEPR = Valence Shell Electron Pair Repulsion Model - Each BOND
More informationChapter 9. Chemical Bonding II: Molecular Geometry and Bonding Theories
Chapter 9 Chemical Bonding II: Molecular Geometry and Bonding Theories Topics Molecular Geometry Molecular Geometry and Polarity Valence Bond Theory Hybridization of Atomic Orbitals Hybridization in Molecules
More informationEXPERIMENT #13 Lewis Structures and Molecular Geometry
OBJECTIVES: EXPERIMENT #13 s and Draw Lewis structures of atoms, ions, and molecules Build models of linear, trigonal planar tetrahedral, trigonal bipyramidal, and octahedral arrangements of electron pairs
More informationExperiment 15. The Valence Shell Electron Pair Repulsion (VSEPR) Theory of Directed Valency: An exercise
Experiment 15 The Valence Shell Electron Pair Repulsion (VSEPR) Theory of Directed Valency: An exercise Attempts to understand and predict the shapes of molecules using either the valencebond theory or
More informationMolecular Geometry and Electron Domain Theory *
OpenStax-CNX module: m12594 1 Molecular Geometry and Electron Domain Theory * John S. Hutchinson This work is produced by OpenStax-CNX and licensed under the Creative Commons Attribution License 2.0 1
More informationUnit 6: Molecular Geometry
Unit 6: Molecular Geometry Molecular Geometry [6-5] the polarity of each bond, along with the geometry of the molecule determines Molecular Polarity. To predict the geometries of more complicated molecules,
More informationVSEPR Theory. Chemistry Warm-up: 1. Pick up a set of the skeleton notes from the first lab table.
Chemistry Warm-up: 1. Pick up a set of the skeleton notes from the first lab table. 2. Complete the words of the week assignment. You need to have answers for Tuesday, Thursday and today. Today s : Draw
More informationIonic and Covalent Bonding
1. Define the following terms: a) valence electrons Ionic and Covalent Bonding the electrons in the highest occupied energy level always electrons in the s and p orbitals maximum of 8 valence electrons
More informationFill in the chart below to determine the valence electrons of elements 3-10
Chemistry 11 Atomic Theory IV Name: Date: Block: 1. Lewis Diagrams 2. VSEPR Lewis Diagrams Lewis diagrams show the bonding between atoms of a molecule. Only the outermost electrons of an atom (called electrons)
More informationChemical Bonds, Molecular Models, and Molecular Shapes
Chemical Bonds, Molecular Models, and Molecular Shapes PRELAB ASSINGMENT Read the entire laboratory write up and answer the following questions before coming to lab. Read the entire laboratory write up
More informationVSEPR Theory. Shapes of Molecules. Molecular Structure or Molecular Geometry
VSEPR Theory VSEPR Theory Shapes of Molecules Molecular Structure or Molecular Geometry The 3-dimensional arrangement of the atoms that make-up a molecule. Determines several properties of a substance,
More informationCHEMICAL BONDING. Valence Electrons. Chapter Ten
CHEMICAL BONDING Chapter Ten Valence Electrons! The electrons occupying the outermost energy level of an atom are called the valence electrons; all other electrons are called the core electrons.! The valence
More informationCh 6 Chemical Bonding
Ch 6 Chemical Bonding What you should learn in this section (objectives): Define chemical bond Explain why most atoms form chemical bonds Describe ionic and covalent bonding Explain why most chemical bonding
More informationCovalent Compounds: Bonding Theories and Molecular Structure
CHM 123 Chapter 8 Covalent Compounds: Bonding Theories and Molecular Structure 8.1 Molecular shapes and VSEPR theory VSEPR theory proposes that the geometric arrangement of terminal atoms, or groups of
More informationLewis Structure and Electron Dot Models
Lewis Structure and Electron Dot Models The Lewis Structure is a method of displaying the electrons present in any given atom or compound. Steps: 1. Make a skeleton structure 2. Count all e- available
More informationCHEMISTRY. Chapter 10 Theories of Bonding and Structure. The Molecular Nature of Matter. Jespersen Brady Hyslop SIXTH EDITION
CHEMISTRY The Molecular Nature of Matter SIXTH EDITION Jespersen Brady Hyslop Chapter 10 Theories of Bonding and Structure Copyright 2012 by John Wiley & Sons, Inc. Molecular Structures Molecules containing
More informationChapter 4. Molecular Structure and Orbitals
Chapter 4 Molecular Structure and Orbitals Chapter 4 Table of Contents (4.1) (4.2) (4.3) (4.4) (4.5) (4.6) (4.7) Molecular structure: The VSEPR model Bond polarity and dipole moments Hybridization and
More information4.2.7 & Shapes, and bond angles for molecules with two, three and four negative charge centers
4.2.7 & 4.2.8 Shapes, and bond angles for molecules with two, three and four negative charge centers The shape of a molecule has an important part to play in determining its chemical (e.g. reactivity and
More informationChemical Bonding II. Molecular Geometry Valence Bond Theory Phys./Chem. Properties Quantum Mechanics Sigma & Pi bonds Hybridization MO theory
Chemical Bonding II Molecular Geometry Valence Bond Theory Phys./Chem. Properties Quantum Mechanics Sigma & Pi bonds ybridization MO theory 1 Molecular Geometry 3-D arrangement of atoms 2 VSEPR Valence-shell
More informationHey, Baby. You and I Have a Bond...Ch. 8
I. IONIC BONDING FUNDAMENTALS A. They form between... 1. A and a a. A to become b. A to become B. How it happens (Let s first focus on two atoms): 1. When a metal and a nonmetal meet, electrons get transferred
More informationA DOT STRUCTURE FOR A LARGER MOLECULE ETHANOL! Count valence electrons
212 A DOT STRUCTURE FOR A LARGER MOLECULE Count valence electrons Pick central atom and draw skeletal structure - central atom is usually the one that needs to gain the most electrons! - skeletal structure
More information11/14/2014. Chemical Bonding. Richard Philips Feynman, Nobel Laureate in Physics ( )
Chemical Bonding Lewis Theory Valence Bond VSEPR Molecular rbital Theory 1 "...he [his father] knew the difference between knowing the name of something and knowing something" Richard Philips eynman, Nobel
More informationCHM151LL: VSEPR and Molecular Geometry Tables
CHM151LL: VSEPR and Molecular Geometry Tables VSEPR Model VALENCE-SHELL ELECTRON-PAIR REPULSION (VSEPR) MODEL Lewis structures show the two-dimensional distribution of atoms and electrons. The molecular
More informationAdapted from CHM 130 Maricopa County, AZ Molecular Geometry and Lewis Dot Formulas Introduction
Adapted from CHM 130 Maricopa County, AZ Molecular Geometry and Lewis Dot Formulas Introduction A chemical bond is an intramolecular (within the molecule) force holding two or more atoms together. Covalent
More informationMOLECULAR MODELS OBJECTIVES
MOLECULAR MODELS OBJECTIVES 1. To learn to draw Lewis structures for common compounds 2. To identify electron pairs as bonding pairs or lone pairs 3. To use electron pair repulsion theory to predict electronic
More informationIntroductory Chemistry
Introductory Chemistry Lab 5: Molecular Models Objectives Understand why molecules have a particular shape Determine the shapes of molecules using the VSEPR model Introduction Why can t you play basketball
More informationMolecular Compounds Compounds that are bonded covalently (like in water, or carbon dioxide) are called molecular compounds
Chapter 8: Covalent Bonding Section 1: Molecular Compounds Bonds are Forces that hold groups of atoms together and make them function as a unit. Two types: Ionic bonds transfer of electrons (gained or
More informationChapter Molecules are 3D. Shapes and Bonds. Chapter 9 1. Chemical Bonding and Molecular Structure
Chapter 9 Chemical Bonding and Molecular Structure 1 Shape 9.1 Molecules are 3D Angle Linear 180 Planar triangular (trigonal planar) 120 Tetrahedral 109.5 2 Shapes and Bonds Imagine a molecule where the
More informationShapes of Molecules. Lewis structures are useful but don t allow prediction of the shape of a molecule.
Shapes of Molecules Lewis structures are useful but don t allow prediction of the shape of a molecule. H O H H O H Can use a simple theory based on electron repulsion to predict structure (for non-transition
More information***Occurs when atoms of elements combine together to form compounds.*****
CHEMICAL BONDING ***Occurs when atoms of elements combine together to form compounds.***** Formation of compounds involve adjustments in the position of one or more valence electrons. PE is lower in bonded
More informationLab Lecture on VSEPR and SPARTAN Chem 141 Lab Dr Abrash 10/3/2011
Q: What is the purpose of this lab? Lab Lecture on VSEPR and SPARTAN Chem 141 Lab Dr Abrash 10/3/2011 To learn two methods to study and predict the shapes of molecules. One is a rule based paper method
More informationChapter 10 Molecular Geometry and Chemical Bonding Theory. Copyright Cengage Learning. All rights reserved. 10 1
Chapter 10 Molecular Geometry and Chemical Bonding Theory Copyright Cengage Learning. All rights reserved. 10 1 Molecular geometry is the general shape of a molecule, as determined by the relative positions
More information* one of these choices is not used
IONIC BONDING REVIEW WORKSHEET Part 1 - Complete each of the following sentences by filling in the appropriate word or phrase from the list below. negative noble gas octet anion positive electrons ions
More informationSubtopic 4.2 MOLECULAR SHAPE AND POLARITY
Subtopic 4.2 MOLECULAR SHAPE AND POLARITY 1 LEARNING OUTCOMES (covalent bonding) 1. Draw the Lewis structure of covalent molecules (octet rule such as NH 3, CCl 4, H 2 O, CO 2, N 2 O 4, and exception to
More information6.1 Intro to Chemical Bonding Name:
6.1 Intro to Chemical Bonding Name: A. Chemical bond Favored by nature because: 3 main types of bonds 1. 2. 3. B. Ionic Bonds C. Covalent Bonds D. Metallic Bond E. Bond Determination RECALL: Electronegativity
More informationLET S FIRST REVIEW IONIC BONDING
COVALENT BONDING LET S FIRST REVIEW IONIC BONDING In an IONIC bond, electrons are lost or gained, resulting in the formation of IONS in ionic compounds. K F K F K F K F K F K F K + F _ The compound potassium
More informationChapter 9 Molecular Geometries. and Bonding Theories
Chapter 9 Molecular Geometries and Bonding Theories Coverage of Chapter 9 9.1 All 9.2 All 9.3 All 9.4 All 9.5 Omit Hybridization Involving d Orbitals 9.6 All 9.7 and 9.8 Omit ALL MOLECULAR SHAPES The shape
More informationChemistry and the material world Lecture 3
Chemistry and the material world 123.102 Lecture 3 Electronic bookkeeping we need a way of finding out in which proportions two or more atoms make up a molecule is it CH 3 or CH 4 or CH 5? counting valence
More informationMolecular Models: The shape of simple molecules and ions
Molecular Models: The shape of simple molecules and ions Background The shape of a molecule is very important when investigating its properties and reactivity. For example, compare CO 2 and SO 2. Carbon
More informationLecture outline: Section 9. theory 2. Valence bond theory 3. Molecular orbital theory. S. Ensign, Chem. 1210
Lecture outline: Section 9 Molecular l geometry and bonding theories 1. Valence shell electron pair repulsion theory 2. Valence bond theory 3. Molecular orbital theory 1 Ionic bonding Covalent bonding
More informationVSEPR. Ch10. Valence Shell Electron Pair Repulsion theory allows you to predict molecular shape. Lewis Dot theory extended to 3 dimensions.
Ch10 VSEPR Valence Shell Electron Pair Repulsion theory allows you to predict molecular shape. Lewis Dot theory extended to 3 dimensions. version 1.5 Nick DeMello, PhD. 2007-2016 Valence Shell Electron
More informationLecture B2 VSEPR Theory
Lecture B2 VSEPR Theory Covalent Bond Theories 1. VSEPR (valence shell electron pair repulsion model). A set of empirical rules for predicting a molecular geometry using, as input, a correct Lewis Dot
More informationChemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals Chapter 1
Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals Chapter 1 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. How to get the book of
More informationLesson Plan. Lesson: Shape of Molecules. Aim: To investigate the shapes of molecules and ions. Learning Outcomes :
Lesson Plan Lesson: Shape of Molecules Aim: To investigate the shapes of molecules and ions Learning Outcomes : At the end of the lesson, students will be able to : 1. explain the Valence Shell Electron
More informationChapter 7 Chemical Bonding
Chapter 7 Chemical Bonding 7.1 Ionic Bonding Octet rule: In forming compounds atoms lose, gain or share electrons to attain a noble gas configuration with 8 electrons in their outer shell (s 2 p 6 ), except
More informationBonding and Molecular Structure - PART 1 - VSEPR
Bonding and Molecular Structure - PART 1 - VSEPR Objectives: 1. Understand and become proficient at using VSEPR to predict the geometries of simple molecules and ions. 2. Become proficient at predicting
More informationCHEMICAL BONDING IONIC BONDS COVALENT BONDS HYDROGEN BONDS METALLIC BONDS
CHEMICAL BONDING IONIC BONDS COVALENT BONDS HYDROGEN BONDS METALLIC BONDS IONIC BONDING When an atom of a nonmetal takes one or more electrons from an atom of a metal so both atoms end up with eight valence
More informationGeneral and Inorganic Chemistry I.
General and Inorganic Chemistry I. Lecture 1 István Szalai Eötvös University István Szalai (Eötvös University) Lecture 1 1 / 29 Outline István Szalai (Eötvös University) Lecture 1 2 / 29 Lewis Formulas
More informationUnit 9: CHEMICAL BONDING
Unit 9: CHEMICAL BONDING 1 Unit 9: Bonding: 1. Electronegativity 2. Intramolecular Bonding 3. Intermolecular Bonding 4. Drawing Lewis Structures 5. Lewis Structures for Polyatomic Ions 6. Exceptions to
More informationChapter 8 : Covalent Bonding. Section 8.1: Molecular Compounds
Chapter 8 : Covalent Bonding Section 8.1: Molecular Compounds What is a molecule? A molecular compound? A molecule is a neutral group of atoms joined together by covalent bonds A molecular compound is
More informationCHAPTER 12 CHEMICAL BONDING
CHAPTER 12 CHEMICAL BONDING Core electrons are found close to the nucleus, whereas valence electrons are found in the most distant s and p energy subshells. The valence electrons are responsible for holding
More informationChapter 12. Chemical Bonding
Chapter 12 Chemical Bonding Chemical Bond Concept Recall that an atom has core and valence electrons. Core electrons are found close to the nucleus. Valence electrons are found in the most distant s and
More informationChapters 8 and 9. Octet Rule Breakers Shapes
Chapters 8 and 9 Octet Rule Breakers Shapes Bond Energies Bond Energy (review): The energy needed to break one mole of covalent bonds in the gas phase Breaking bonds consumes energy; forming bonds releases
More informationFor this you need to know covalent bonds, Lewis dots, electronegativity, geometric shapes, duet & octet, single/double/triple bonds, etc...
Lewis Structure Lab For this you need to know covalent bonds, Lewis dots, electronegativity, geometric shapes, duet & octet, single/double/triple bonds, etc... I can t assume you have had all these, so
More informationMolecular Geometry and Chemical Bonding Theory
Molecular Geometry and Chemical Bonding Theory The Valence -Shell Electron -Pair Repulsion (VSEPR) Model predicts the shapes of the molecules and ions by assuming that the valence shell electron pairs
More informationCh. 12 Section 1: Introduction to Chemical Bonding
Name Period Date Chemical Bonding & Intermolecular Forces (Chapter 12, 13 &14) Fill-in the blanks during the PowerPoint presentation in class. Ch. 12 Section 1: Introduction to Chemical Bonding Chemical
More informationChemical Bonding Chapter 8
Chemical Bonding Chapter 8 Get your Clicker, 2 magnets, goggles and your handouts Nov 15 6:15 PM Recall that: Ionic-Involves the transfer of electrons - forms between a metal and a nonmetal Covalent-Involves
More informationShapes of Molecules VSEPR
Shapes of Molecules In this section we will use Lewis structures as an introduction to the shapes of molecules. The key concepts are: Electron pairs repel each other. Electron pairs assume orientations
More informationUnit Six --- Ionic and Covalent Bonds
Unit Six --- Ionic and Covalent Bonds Electron Configuration in Ionic Bonding Ionic Bonds Bonding in Metals Valence Electrons Electrons in the highest occupied energy level of an element s atoms Examples
More informationChapter 9: Molecular Geometries and Bonding Theories Learning Outcomes: Predict the three-dimensional shapes of molecules using the VSEPR model.
Chapter 9: Molecular Geometries and Bonding Theories Learning Outcomes: Predict the three-dimensional shapes of molecules using the VSEPR model. Determine whether a molecule is polar or nonpolar based
More informationCovalent Bonds Ch. Why do atoms bond? Atoms want noble gas configuration ( ) For bonds there is a transfer of electrons to get an octet of electrons
Covalent Bonds Ch. Why do atoms bond? Atoms want noble gas configuration ( ) For bonds there is a transfer of electrons to get an octet of electrons For covalent bonds there is a of electrons to get an
More informationCHAPTER TEN MOLECULAR GEOMETRY MOLECULAR GEOMETRY V S E P R CHEMICAL BONDING II: MOLECULAR GEOMETRY AND HYBRIDIZATION OF ATOMIC ORBITALS
CHAPTER TEN CHEMICAL BONDING II: AND HYBRIDIZATION O ATOMIC ORBITALS V S E P R VSEPR Theory In VSEPR theory, multiple bonds behave like a single electron pair Valence shell electron pair repulsion (VSEPR)
More informationAP Chemistry - Problem Drill 15: Lewis Structures and VSEPR Theory
AP Chemistry - Problem Drill 15: Lewis Structures and VSEPR Theory No. 1 of 10 1. Which shape would have sp 3 hybridization? (A) Linear (B) Bent (C) Tetrahedron (D) Trigonal planar (E) Octahedron C. Correct.
More informationChapter 6. Chemical Bonding
Chapter 6 Chemical Bonding Section 6.1 Intro to Chemical Bonding 6.1 Objectives Define chemical bond. Explain why most atoms form chemical bonds. Describe ionic and covalent bonding. Explain why most chemical
More informationChemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals
Chemical Bonding II: Molecular Geometry and Hybridization of Atomic Orbitals Chapter 10 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 Valence shell electron
More informationChapter 9. Molecular Geometry and Bonding Theories
Chapter 9. Molecular Geometry and Bonding Theories 9.1 Molecular Shapes Lewis structures give atomic connectivity: they tell us which atoms are physically connected to which atoms. The shape of a molecule
More informationChapter 9 The Shapes of Molecules Cocaine
Chapter 9 The Shapes of Molecules 1 Cocaine 10.1 Depicting Molecules & Ions with Lewis Structures 2 Number of Covalent Bonds 3 The number of covalent bonds can be determined from the number of electrons
More informationH O H C H H N H H. Valence Shell Electron Pair Repulsion: Predicting Shape & Polarity
Valence Shell Electron Pair Repulsion: Predicting Shape & Polarity BJECTIVES Students will develop the ability to: 1. Predict the arrangement that valence e pairs assume around an atom (e pair geometry)
More information