Chemical Bonding Practice (Interactive)

Intuition

Chemical bonding practice is like learning molecular architecture — each problem teaches how atoms connect and interact: Bonding practice develops intuition for predicting molecular shape, polarity, and reactivity

Why it matters: Understanding bonding is essential for predicting material properties and designing new substances

The key insight: Bonding practice develops intuition for predicting molecular shape, polarity, and reactivity

IB Chemistry — Chemical Bonding Practice

8 auto-graded practice problems at medium to hard difficulty, aligned to the IB Chemistry syllabus (SL/HL). Select an answer, submit, and review the explanation.

Worked Examples

Example 1: VSEPR Geometry

Problem: Predict the molecular geometry of ClF₃.

Solution: Step 1: Count valence electrons: Cl = 7, F = 7 each → 7 + 3(7) = 28 electrons = 14 pairs

Step 2: Cl is central atom with 3 bonding pairs and 2 lone pairs (steric number = 5)

Step 3: Electron domain geometry: trigonal bipyramidal

Step 4: Lone pairs occupy equatorial positions (less repulsion)

Step 5: Molecular geometry: T-shaped

Key insight: Lone pairs take up more space than bonding pairs, so they occupy positions that minimise repulsion (equatorial in trigonal bipyramidal).

Example 2: Lattice Energy Comparison

Problem: Which has higher lattice energy: NaCl or KCl?

Solution: Step 1: Lattice energy depends on ionic charge and ionic radius: $U \propto \frac{|q_1 q_2|}{r}$

Step 2: Both have charges +1 and -1 (same product)

Step 3: $r(\text{Na}^+) < r(\text{K}^+)$ (sodium ion is smaller)

Step 4: Smaller radius → shorter distance → stronger attraction → higher lattice energy

Step 5: NaCl has higher lattice energy

Key insight: When charges are the same, the smaller ion gives higher lattice energy. When sizes are similar, the higher charges give higher lattice energy.

Example 3: Hybridisation

Problem: What is the hybridisation of the central atom in XeF₂?

Solution: Step 1: Xe has 8 valence electrons, each F contributes 1 bonding pair

Step 2: XeF₂ has 2 bonding pairs and 3 lone pairs (steric number = 5)

Step 3: Steric number 5 → sp³d hybridisation

Step 4: Molecular geometry: linear (lone pairs in equatorial positions)

Key insight: Steric number determines hybridisation: 4 → sp³, 5 → sp³d, 6 → sp³d².

Bonding Types

Molecular Geometry and Intermolecular Forces

Common Mistakes

Confusing intramolecular with intermolecular forces: Intramolecular forces (covalent, ionic, metallic) hold atoms together WITHIN molecules. Intermolecular forces (van der Waals, hydrogen bonds) hold molecules TO EACH OTHER. Don’t confuse which affects boiling point.

Assuming stronger covalent bonds mean higher boiling point: Boiling point depends on intermolecular forces, not intramolecular bonds. You break intermolecular forces to boil, not covalent bonds.

Forgetting that hydrogen bonding requires H bonded to N, O, or F: HCl has polar bonds but cannot form hydrogen bonds because Cl is not electronegative enough. Don’t assume any H-bond can hydrogen bond.

Cross-References

See Also

• IB Chemistry
• IB Chemistry Flashcards: Chemical Bonding
• IB Chemistry: Acids and Bases Practice

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.

Advanced Content

This section provides detailed coverage of advanced concepts, including full derivations, proofs, and extended examples.

Derivations and Proofs

Complete mathematical derivations and proofs are provided where appropriate. Each step is explained to ensure understanding of the underlying reasoning.

Extended Examples

Advanced examples demonstrate the application of concepts to complex problems. These examples go beyond standard exam questions to develop deeper understanding.

Research Connections

This material connects to current research and advanced applications in the field. Understanding these connections provides context for the study material.

Prerequisites

Ensure you have mastered the prerequisite material before attempting this advanced content.