chapter 1 electronic structure and covalent bonding dr. sujatha krishnaswamy chemistry faculty...
TRANSCRIPT
![Page 1: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/1.jpg)
Chapter 1
Electronic Structure and Covalent Bonding
Dr. Sujatha KrishnaswamyChemistry Faculty
Chandler Gilbert Community College
![Page 2: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/2.jpg)
What is organic chemistry?
“Organic” – until mid 1800’s referred to compounds from living sources (mineral sources were “inorganic”)
Wöhler in 1828 showed that urea, an organic compound, could be made from a minerals
2
![Page 3: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/3.jpg)
3
Today, organic compounds are those based on carbon structures.
Organic chemistry is a study of their structures and reactions
Includes biological molecules, drugs, solvents, dyes
Does not include metal salts and materials (inorganic)
Does not include materials of large repeating molecules without sequences (polymers)
![Page 4: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/4.jpg)
Atomic Structure
Structure of an atom Positively charged nucleus (very dense, protons and neutrons) and smal
(10-15 m) Negatively charged electrons are in a cloud (10-10 m) around nucleus Neutral neutrons Electrons forms chemical bonds. Atomic number – number of protons in the nucleus Mass number – the sum of protons and neutrons in an atom Isotopes have the same atomic number but different mass number Atomic weight – average weighted mass of all atoms in an element Molecular weight – sum of atomic weights of all atoms in a molecule
4
![Page 5: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/5.jpg)
Distribution of Electrons in an Atom Quantum mechanics uses the mathematical equation
of wave motions to characterize the motion of an electron around a nucleus.
Wave functions or orbitals tell us the energy of the electron and the volume of space around the nucleus where an electron is most likely to be found.
The atomic orbital closer to the nucleus has the lowest energy.
Degenerate orbitals have the same energy. Give an example of degenerate orbitals.
5
![Page 6: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/6.jpg)
Distribution of Electrons in an Atom
6
![Page 7: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/7.jpg)
7
Electronic Configuration of Carbon
Atomic Number = 6
2p
2s
1s
![Page 8: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/8.jpg)
8
Electronic Configuration of Carbon
Atomic Number = 6
2p
2s
1s
![Page 9: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/9.jpg)
Chemical Bonding Theory Van't Hoff and Le Bel proposed that the four
bonds of carbon have specific spatial directions
Atoms surround carbon as corners of a tetrahedron
9
![Page 10: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/10.jpg)
10
The Covalent Bond Some atoms form a chemical bond by sharing pairs of
electrons between them. A covalent bond consists of a pair of electrons shared
between two atoms.
![Page 11: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/11.jpg)
11
![Page 12: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/12.jpg)
Polar Covalent Bonds
12
![Page 13: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/13.jpg)
13
Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons.
![Page 14: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/14.jpg)
Bond Polarity
14
![Page 15: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/15.jpg)
![Page 16: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/16.jpg)
Which bond is more polar?
16
![Page 17: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/17.jpg)
Problem 6
![Page 18: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/18.jpg)
18
![Page 19: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/19.jpg)
Dipole Moments Dipole moment () - Net molecular polarity, due to difference in
summed charges
dipole moment (D) = = e x d
(e) : magnitude of the charge on the atom(d) : distance between the two charges
19
![Page 20: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/20.jpg)
Absence of Dipole Moments
In symmetrical molecules, the dipole moments of each bond has one in the opposite direction
The effects of the local dipoles cancel each other
20
![Page 21: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/21.jpg)
21
Useful information for writing Lewis structures
Page 13 Problem 13
![Page 22: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/22.jpg)
22
Write Lewis structures for -
Ethane, C2H6
Ethene, C2H4
Ethyne, C2H2
Acetic acid, CH3COOH
Ethyl amine, CH3CH2NH2
![Page 23: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/23.jpg)
23
Formal Charges
![Page 24: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/24.jpg)
Problem 11
![Page 25: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/25.jpg)
Formal charge observed with common bonding patterns
25
![Page 26: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/26.jpg)
26
sp3 Hybridization in Methane
![Page 27: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/27.jpg)
27
sp3 Hybridization in Ethane
![Page 28: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/28.jpg)
28
sp2 Hybridization in Ethylene
![Page 29: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/29.jpg)
29
sp2 Hybridization in Acetylene
![Page 30: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/30.jpg)
Why cyclopentyne does not exist?
30
![Page 31: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/31.jpg)
31
![Page 32: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/32.jpg)
Problem 28
![Page 33: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/33.jpg)
Problem 29
![Page 34: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/34.jpg)
Bond Lengths and Bond Strengths
34
![Page 35: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/35.jpg)
Drawing Organic Structures
Expanded structure Condensed structure Line angle structure
35
![Page 36: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/36.jpg)
36
![Page 37: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/37.jpg)
37
![Page 38: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/38.jpg)
38
![Page 39: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/39.jpg)
Problem 14
![Page 40: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/40.jpg)
Problem 18
![Page 41: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/41.jpg)
Draw line angle structures for
41
![Page 42: Chapter 1 Electronic Structure and Covalent Bonding Dr. Sujatha Krishnaswamy Chemistry Faculty Chandler Gilbert Community College](https://reader035.vdocuments.us/reader035/viewer/2022062519/5697bff91a28abf838cbf8cd/html5/thumbnails/42.jpg)
Problem 17