amazon.co.ukAtomic Structure and Bonding
A-Level Chemistry revision: Atomic Structure and Bonding. Learning objectives, key points, worked examples and practice questions across AQA, Edexcel, OCR, WJEC and CCEA.
📌 Key Points
Key Fact: Atomic structure: p⁺, n⁰, e⁻; isotopes = same Z, different A; electron config: 1s^22s^22p⁶...
Key Fact: Ionisation energy: increases across period (↑Z_eff), decreases down group (↑shielding, ↑n)
Key Fact: Ionic: metal + non-metal, electron transfer, lattice; Covalent: non-metal + non-metal, sharing
Key Fact: Electronegativity (Pauling): increases across, decreases down; >1.7 ionic, <0.4 non-polar covalent
Key Fact: VSEPR: electron pairs repel; 2bp -> linear, 3bp -> trigonal planar, 4bp -> tetrahedral, lone pairs reduce angles
Key Fact: IMFs: London (all molecules, ∝ electrons), dipole-dipole (polar), H-bonding (H on N,O,F)
Key Fact: Properties: Giant ionic/covalent/metallic -> high MP; Simple molecular -> low MP; H-bonding -> higher MP/BP
🎯 Learning Objectives
- Describe atomic structure: subatomic particles, isotopes, electron configuration
- Explain ionisation energies and trends across periods/down groups
- Understand ionic, covalent, metallic, and hydrogen bonding
- Use electronegativity to predict bond polarity and type
- Describe shapes of molecules using VSEPR theory
- Understand intermolecular forces: van der Waals, dipole-dipole, hydrogen bonding
- Relate structure and bonding to physical properties (melting point, conductivity, solubility)
💡 Worked Example
Exam-Style Question
Question: Explain why H₂O has a higher boiling point than H₂S despite similar molecular mass
Model Answer:
H₂O has H-bonding (O is highly electronegative, lone pairs); H₂S has only dipole-dipole and London forces. H-bonding is much stronger -> more energy to separate molecules -> higher BP
❓ Practice Questions
Questions:
- Write electron configuration of Fe^2⁺ (Z=26)
- Predict shape and bond angle of NH₃, CO₂, SF₆
- Rank boiling points: CH₄, NH₃, H₂O, HF -- explain
- Why does MgO have higher MP than NaCl?
- Explain conductivity of graphite vs diamond
🎬 Video Resources
- Atomic Structure and Bonding - Overview -- YouTube Search
- Atomic Structure and Bonding - Exam Questions -- YouTube Search
📄 Past Papers & Exam Resources
🔗 Further Reading & Resources
- Physics & Maths Tutor - Atomic Structure and Bonding -- Free notes, worksheets, and past paper questions by topic
- Dr Frost Maths - Atomic Structure and Bonding -- Free resources, slides, and interactive questions
- BBC Bitesize - Atomic Structure and Bonding -- BBC Bitesize revision resources
📚 Lesson Plan (50 minutes)
- Starter (5 min): Recall prior knowledge of atomic structure and bonding with quick questions.
- Teaching (15 min): Work through each of the learning objectives, explaining principles step by step.
- Key points review (5 min): Revisit the key points together, confirming understanding.
- Worked example (10 min): Model the example question: Explain why H₂O has a higher boiling point than H₂S despite similar molecular mass. Solution: H₂O has H-bonding (O is highly electronegative, lone pairs); H₂S has only dipole-dipole and London forces. H-bonding is much stronger -> more energy to separate molecules -> higher BP
- Practice (10 min): Students attempt the practice questions independently; circulate and support.
- Plenary (5 min): Review answers and address misconceptions.
🏠 Homework
- Write electron configuration of Fe^2⁺ (Z=26)
- Predict shape and bond angle of NH₃, CO₂, SF₆
- Rank boiling points: CH₄, NH₃, H₂O, HF -- explain
- Why does MgO have higher MP than NaCl?
- Explain conductivity of graphite vs diamond
🧾 Assessment
Check practice answers against the model answer; use the built-in practice questions as formative assessment.