Study guides › C/P › General Chemistry
Bonding & Molecular Geometry
This chapter covers how atoms bond and how molecules take shape. You will draw Lewis structures, assign formal charges and resonance, predict VSEPR geometry, polarity, and hybridization, and connect bond order to length and energy.
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What this chapter covers
- Types of Bonds & Electronegativity. Classifying a bond as ionic, polar covalent, or nonpolar covalent, and ranking lattice energies, is basic MCAT vocabulary.
- Lewis Structures, Formal Charge & Resonance. Every geometry, polarity, and reactivity question starts from a correct Lewis structure.
- VSEPR & Molecular Geometry. Counting electron domains gives the shape, and the shape decides polarity, hybridization, and reactivity.
- Polarity, Hybridization & Sigma/Pi Bonds. Shape decides polarity, and domain count decides hybridization. Both are asked with organic and inorganic examples.
- Bond Order, Length & Energy. Bond order predicts bond length and strength, and bond energies let you estimate reaction enthalpies.
Key points to know
- ΔEN sets bond type: nonpolar, polar covalent, or ionic
- Ionic solids: high melting point, brittle, conduct only when molten or dissolved
- Valence electrons set the total; the least electronegative atom is central
- Formal charge = V − nonbonding − bonds; the sum equals the net charge
- Count domains: bonds (any order) plus lone pairs on the central atom
- Lone pairs repel more, so angles fall: 109.5° → 107° → 104.5°
- Polar molecule = polar bonds that do not cancel by symmetry
- Domains 2, 3, 4, 5, 6 map to sp, sp², sp³, sp³d, sp³d²
Try a practice question
Which bond is the most polar?
- C–H
- N–H
- O–H
- H–F
Show the answer
D. Polarity grows with ΔEN. Fluorine (4.0) has the largest electronegativity difference from hydrogen (2.1), so H–F is the most polar. C–H is nearly nonpolar.
Common questions
What does this chapter cover?
Bonding & Molecular Geometry covers Types of Bonds & Electronegativity, Lewis Structures, Formal Charge & Resonance, VSEPR & Molecular Geometry, Polarity, Hybridization & Sigma/Pi Bonds, Bond Order, Length & Energy.
What should I know first?
ΔEN sets bond type: nonpolar, polar covalent, or ionic Ionic solids: high melting point, brittle, conduct only when molten or dissolved Valence electrons set the total; the least electronegative atom is central
25 original practice questions accompany this chapter in the app. Spaced review brings missed ideas back at the right time; it helps memory but cannot promise you will not miss an idea again.