Part 1 Introduction and Review

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Natural Chemistry , 5 th Edition L. G. Swim, Jr. Section 1 Introduction and Review Jo Blackburn Richland College, Dallas, TX Dallas County Community College District ã 2003, Prentice Hall

=> Definitions Old: "got from living creatures" New: "science of carbon mixes" From inorganic to natural, Wöhler, 1828 Chapter 1

=> Atomic Structure protons, neutrons, and electrons isotopes Chapter 1

2 s orbital (circular) => 2 p orbital Atomic Orbitals Chapter 1

 => Electronic Configurations Aufbau guideline: Place electrons in least vitality orbital first. Hund's control: Equal vitality orbitals are half-filled, then filled.   Chapter 1

Table 1-1 => Chapter 1

=> Bond Formation Ionic holding: electrons are exchanged. Covalent holding: electron match is shared. Part 1

Lewis Structures Bonding electrons Nonbonding electrons or solitary sets Satisfy the octet run the show! => Chapter 1

Multiple Bonding => Chapter 1

=> Dipole Moment Amount of electrical charge x bond length. Charge partition appeared by electrostatic potential guide (EPM). Red shows a somewhat negative district and blue demonstrates a halfway positive locale. Part 1

Electronegativity and Bond Polarity Greater  EN implies more prominent extremity => Chapter 1

=> Calculating Formal Charge For every iota in a legitimate Lewis structure: Count the quantity of valence electrons Subtract all its nonbonding electrons Subtract half of its holding electrons Chapter 1

X => Ionic Structures Chapter 1

Resonance Only electrons can be moved (generally solitary sets or pi electrons). Cores positions and bond points continue as before. The quantity of unpaired electrons continues as before. Reverberation causes a delocalization of electrical charge. Case => Chapter 1

Resonance Example The genuine structure is a reverberation half and half. All the bond lengths are the same. Every oxygen has a - 1/3 electrical charge. => Chapter 1

Major Resonance Form has whatever number octets as could be expected under the circumstances. has whatever number bonds as would be prudent. has the negative charge on the most electronegative molecule. has as meager charge division as could be expected under the circumstances. Illustration => Chapter 1

real minor, carbon does not have octet. => Major Contributor? Part 1

Full auxiliary recipe (no solitary sets appeared) Line-edge equation Condensed basic equation Molecular recipe Empirical recipe CH 3 COOH C 2 H 4 O 2 CH 2 O => Chemical Formulas Chapter 1

Calculating Empirical Formulas Given % organization for every component, accept 100 grams. Change over the grams of every component to moles. Isolate by the littlest moles to get proportion. Sub-atomic recipe might be a numerous of the exact equation. => Chapter 1

=> Arrhenius Acids and Bases Acids separate in water to give H 3 O + particles. Bases separate in water to give OH - particles. K w = [H 3 O + ][OH - ] = 1.0 x 10 - 14 at 24°C pH = - log [H 3 O + ] Strong acids and bases are 100% separated. Part 1

conjugate corrosive conjugate base corrosive base => Br Ø nsted-Lowry Acids and Bases Acids can give a proton. Bases can acknowledge a proton. Conjugate corrosive base sets. Section 1

p K a 4.74 p K b 3.36 p K b 9.26 p K a 10.64 => Acid and Base Strength Acid separation steady, K a Base separation consistent, K b For conjugate sets, ( K a )( K b ) = K w Spontaneous corrosive base responses continue from more grounded to weaker. Section 1

Determining Relative Acidity Electronegativity Size Resonance adjustment of conjugate base => Chapter 1

=> Electronegativity As the cling to H turns out to be more energized, H turns out to be more positive and the bond is simpler to break. Part 1

=> Size As size expands, the H is all the more inexactly held and the bond is less demanding to break. A bigger size additionally settles the anion. Part 1

=> Resonance Delocalization of the negative charge on the conjugate base will settle the anion, so the substance is a more grounded corrosive. More reverberation structures generally mean more noteworthy adjustment. Part 1

nucleophile electrophile => Lewis Acids and Bases Acids acknowledge electron sets = electrophile Bases give electron sets = nucleophile Chapter 1

End of Chapter 1 Chapter 1