Study Guide: Concept 1 - Introduction to Bonding
Key Topics and Objectives
1. Forces Between Substances vs. Within a Substance
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Intermolecular forces: Forces between molecules (e.g., hydrogen bonding, dipoledipole, London dispersion).
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Intramolecular forces: Forces within a molecule (e.g., ionic, covalent, and metallic
bonds).
2. Bonding as a Spectrum
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Bonding is not just "ionic" or "covalent" but exists on a spectrum depending on
electronegativity differences.
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Pure covalent (nonpolar) → Polar covalent → Ionic
3. Chemical Bonds, Reactions, and Compounds
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Chemical bonds: Forces holding atoms together.
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Chemical reactions: Process where substances change into new substances.
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Compounds: Substances formed when two or more elements chemically bond.
4. Why Atoms Form Chemical Bonds
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Atoms bond to achieve stability (noble gas electron configuration).
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The Octet Rule states that atoms gain, lose, or share electrons to reach eight
valence electrons.
5. Chemical Formulas: Ionic vs. Covalent
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Ionic compounds: Metal + Nonmetal (transfer of electrons).
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Covalent compounds: Nonmetal + Nonmetal (sharing of electrons).
6. Covalent vs. Ionic Bonds
Property
Covalent Bonds Ionic Bonds
Electron Transfer? Shared
Transferred
Types of Elements Nonmetals
Metals & Nonmetals
Property
Covalent Bonds Ionic Bonds
Conductivity
Poor
Good (when dissolved)
Melting Point
Lower
Higher
7. Properties of Covalent vs. Ionic Compounds
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Covalent compounds: Lower melting/boiling points, soft, poor conductors.
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Ionic compounds: High melting/boiling points, hard, conduct electricity in water.
8. Predicting Compound Properties from Chemical Formulas
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Look at elements involved: Metals → Ionic, Nonmetals → Covalent.
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Check the electronegativity difference:
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0.0 - 0.4 → Nonpolar covalent
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0.5 - 1.7 → Polar covalent
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1.8+ → Ionic
9. Identifying Bond Type
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Use electronegativity difference to determine bond type.
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Recognize bonding patterns based on descriptions, pictures, and examples.
10. Periodic Table and Bonding Trends
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Oxidation number: Predicts how many electrons an element will gain or lose.
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Bonding tendencies:
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Group 1 & 2: Likely to form ionic bonds.
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Groups 14-17: Likely to form covalent bonds.
Chemical bond: Attraction holding atoms together.
Electronegativity: Measure of an atom’s ability to attract electrons.
Octet rule: Atoms tend to gain, lose, or share electrons to get 8 valence electrons.
Molecule: Group of atoms bonded covalently.
Salt: Ionic compound.
Crystal lattice: 3D structure of ions in an ionic compound.