11. Shapes of Molecules — A Level Chemistry 🎯 Learning Outcomes Candidates should be able to: State and explain the shapes of, and bond angles in, molecules by using VSEPR theory, including CO₂ (linear, 180°), BF₃ (trigonal planar, 120°), CH₄ (tetrahedral, 109.5°), NH₃ (pyramidal, 107°), H₂O (non-linear, 104.5°), PF₅ (trigonal bipyramidal, 120° and 90°) and…
10. Covalent & Coordinate Bonding — A Level Chemistry 🎯 Learning Outcomes Candidates should be able to: Define covalent bonding, and describe covalent bonding in H₂, O₂, N₂, Cl₂, HCl, CO₂, NH₃, CH₄, C₂H₆ and C₂H₄; understand that Period 3 elements can expand their octet (e.g. SO₂, PCl₅, SF₆); describe coordinate (dative covalent) bonding, including…
9. Metallic Bonding — A Level Chemistry 🎯 Learning Outcomes By the end of this chapter, students should be able to: Define metallic bonding and draw an illustration to represent it. 1 What Is Metallic Bonding? ▾ In a metal, atoms are packed closely together in a regular arrangement called a lattice. Metal atoms in…
8. Ionic Bonding — A Level Chemistry 🎯 Learning Outcomes Candidates should be able to: Define ionic bonding. Describe ionic bonding, using the examples of sodium chloride, magnesium chloride and calcium fluoride, including the use of ‘dot-and-cross’ diagrams. 1 What Is Ionic Bonding? ▾ An ionic bond is the strong electrostatic attraction between positively charged…
🎯 Learning outcomes After completing this lesson, you should be able to: define electronegativity explain the factors influencing the electronegativities of the elements state and explain the trends in electronegativity across a period and down a group of the Periodic Table use differences in Pauling electronegativity values to predict the formation of ionic and covalent…
🎯 Learning outcomes After completing this lesson, you should be able to: describe, in simple terms, the lattice structure of a crystalline solid which is: giant ionic, including sodium chloride and magnesium oxide simple molecular, including iodine, buckminsterfullerene (C₆₀) and ice giant molecular, including silicon(IV) oxide, graphite and diamond giant metallic, including copper describe, interpret…
🎯 Learning outcomes After completing this lesson, you should be able to: explain the origin of pressure in a gas in terms of collisions between gas molecules and the walls of the container understand that ideal gases have zero particle volume and no intermolecular forces of attraction state and use the ideal gas equation, pV…
🎯 Learning outcomes After completing this lesson, you should be able to: explain and use the terms catalyst and catalysis explain that, in the presence of a catalyst, a reaction has a different mechanism — one of lower activation energy explain this catalytic effect in terms of the Boltzmann distribution construct and interpret a reaction…
🎯 Learning outcomes After completing this lesson, you should be able to: define activation energy, EA, as the minimum energy required for a collision to be effective sketch and use the Boltzmann distribution to explain the significance of activation energy explain qualitatively, in terms both of the Boltzmann distribution and of the frequency of effective…
🎯 Learning outcomes After completing this lesson, you should be able to: explain and use the terms rate of reaction, frequency of collisions, effective collisions and non-effective collisions explain qualitatively, in terms of the frequency of effective collisions, the effect of concentration and pressure changes on the rate of a reaction use experimental data to…
5.2 Hess’s Law — A Level Chemistry Learning outcomes Candidates should be able to: apply Hess’s Law to construct simple energy cycles carry out calculations using cycles and relevant energy terms, including: determining enthalpy changes that cannot be found by direct experiment use of bond energy data Before you start You can’t set a match…
5.1 Enthalpy Change — A Level Chemistry Learning outcomes Candidates should be able to: understand that chemical reactions are accompanied by enthalpy changes and these changes can be exothermic (ΔH is negative) or endothermic (ΔH is positive) construct and interpret a reaction pathway diagram, in terms of the enthalpy change of the reaction and of…
Learning outcomes By the end of this topic, you should be able to: Analyse mass spectra in terms of m/e values and isotopic abundances (knowledge of the working of the mass spectrometer is not required). Calculate the relative atomic mass of an element given the relative abundances of its isotopes, or its mass spectrum. Deduce…
22.1 INFRARED SPECTROSCOPY Learning Outcomes Candidates should be able to: Analyse an infrared spectrum of a simple molecule to identify functional groups. 1 What Is Infrared Spectroscopy? In infrared (IR) spectroscopy, a sample is irradiated — exposed to radiation — with electromagnetic waves from the infrared region of the spectrum. The instrument used is a…
Particles in Atoms & Atomic Radius 🎯 Learning outcomes Candidates should be able to: Understand that atoms are mostly empty space surrounding a very small, dense nucleus that contains protons and neutrons; electrons are found in shells in the empty space around the nucleus Identify and describe protons, neutrons and electrons in terms of their…