LESSON OBJECTIVE: Understand the mechanism of electrophilic addition reactions for alkenes and predict the products of these reactions (applying Markovnikov’s rule when appropriate). In this lesson we introduce the homologous series of the alkenes by investigating alkene addition reactions, the mechanism by which this electrophilic addition occurs and the effect the carbocation stability and Markovnikov’s rule will have on predicting the product of these types of reactions. This is lesson six in our organic chemistry series of Unit 15: Hydrocarbons (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 15.2 Alkenes a) describe the chemistry of alkenes as exemplified, where relevant, by the following reactions of ethene and propene (including the Markovnikov addition of asymmetric electrophiles using propene as an example): (i) addition of hydrogen, steam, hydrogen halides and halogens b) describe the mechanism of electrophilic addition in alkenes, including using bromine/ethene and hydrogen bromide/propene as examples c) describe and explain the inductive effects of alkyl groups on the stability of cations formed during electrophilic addition

In this lesson we discuss how to calculate enthalpy changes using the equation ΔH=–mcΔT, specific heat capacity and the concept of calorimetry as an experimental technique. This is lesson sixteen in our physical chemistry series for Unit 5: Chemical Energetics (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Understand how to calculate the enthalpy change of a reaction from experimental data obtained via calorimetry. LEARNING OUTCOMES (from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum): 5.1 Enthalpy change, ΔH c) calculate enthalpy changes from appropriate experimental results, including the use of the relationship ΔH = –mcΔT

LESSON OBJECTIVE: Use orbital hybridisation to determine the shape of an organic molecule and understand and identify different types of structural isomerism and stereoisomerism. In this lesson we discuss how hybridisation, molecular geometries and sigma and pi bonds are linked to organic structure and formulas. We then introduce isomerism by looking at the different types of structural isomerism (position, functional group and chain) and stereoisomerism (cis-trans and optical). This is lesson two in our organic chemistry unit for Unit 14: An introduction to organic chemistry (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 14.3 Shapes of organic molecules; σ and π bonds a) (i) describe and explain the shape of, and bond angles in, the ethane and ethene molecules a) in terms of σ and π bonds (ii) predict the shapes of, and bond angles in, other related molecules 14.4 Isomerism: structural and stereoisomerism a) describe structural isomerism and its division into chain, positional and functional group isomerism b) describe stereoisomerism and its division into geometrical (cis-trans) and optical isomerism (use of E, Z nomenclature is acceptable but is not required) c) describe geometrical (cis-trans) isomerism in alkenes, and explain its origin in terms of restricted rotation due to the presence of π bonds d) explain what is meant by a chiral centre and that such a centre normally gives rise to optical isomerism e) identify chiral centres and geometrical (cis-trans) isomerism in a molecule of given structural formula

LESSON OBJECTIVE: Describe reactions of period 3 elements with oxygen and water and investigate the periodicity of Period 3 oxides. In this lesson we link the concept of periodicity to chemical properties by investigating the formation and reactions of Period 3 oxides. This is lesson two in our inorganic chemistry series for Unit 9: The Periodic Table: chemical periodicity (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 9.2 Periodicity of chemical properties of the elements in Period 3 a) describe the reactions, if any, of the elements with oxygen (to give Na2O, MgO, Al2O3, P4O10, SO2, SO3), chlorine (to give NaCl, MgCl2, Al2Cl6, SiCl4, PCl5) and water (Na and Mg only) b) state and explain the variation in oxidation number of the oxides (sodium to sulfur only) and chlorides (sodium to phosphorus only) in terms of their outer shell (valence shell) electrons c) describe the reactions of the oxides with water (treatment of peroxides and superoxides is not required) d) describe and explain the acid/base behaviour of oxides and hydroxides including, where relevant, amphoteric behaviour in reactions with acids and bases (sodium hydroxide only) f) interpret the variations and trends in 9.2(b), ©, (d) and (e) in terms of bonding and electronegativity g) suggest the types of chemical bonding present in chlorides and oxides from observations of their chemical and physical properties 9.1 Periodicity of physical properties of the elements in Period 3 e) explain the strength, high melting point and electrical insulating properties of ceramics in terms of their giant structure; to include magnesium oxide, aluminium oxide and silicon dioxide

In this lesson we give an overview of the three types of chemical bonding (ionic, covalent and metallic) and an introduction into how VSEPR theory dictates molecular geometries. This is lesson eight in our physical chemistry series for Unit 3: Chemical Bonding (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Understand how ionic, covalent and metallic bonds form. Rationalise molecular geometries using VSEPR theory. Learning Outcomes (from the Cambridge AS Chemistry Curriculum 2019-2021): 3.1 Ionic bonding a) describe ionic bonding, using the examples of sodium chloride, magnesium oxide and calcium fluoride, including the use of ‘dot-and- cross’ diagrams 3.2 Covalent bonding and co-ordinate (dative covalent) bonding including shapes of simple molecules a) describe, including the use of ‘dot-and-cross’ diagrams: (i) covalent bonding, in molecules such as hydrogen, oxygen, chlorine, hydrogen chloride, carbon dioxide, methane, ethene (ii) co-ordinate (dative covalent) bonding, such as in the formation of the ammonium ion and in the Al2Cl6 molecule c) explain the shapes of, and bond angles in, molecules by using the qualitative model of electron-pair repulsion (including lone pairs), using as simple examples BF3 (trigonal planar), CO2 (linear), CH4 (tetrahedral), NH3 (pyramidal), H2O (non-linear), SF6 (octahedral), PF5 (trigonal bipyramidal) 3.4 Metallic bonding a) describe metallic bonding in terms of positive ions surrounded by delocalised electrons

LESSON OBJECTIVE: Investigate substitution and elimination reactions of halogenoalkanes and describe some of their uses and pollution. In this lesson we investigate the homologous series of halogenoalkanes but introducing key reactions they undergo (substitution and elimination), describe their uses, how they act as pollutants and the detrimental effect they have had on the ozone layer. This is lesson eight in our organic chemistry series of Unit 16: Halogen derivatives (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 16.1 Halogenoalkanes a) recall the chemistry of halogenoalkanes as exemplified by: (i) the following nucleophilic substitution reactions of bromoethane: hydrolysis, formation of nitriles, formation of primary amines by reaction with ammonia (ii) the elimination of hydrogen bromide from 2-bromopropane 16.2 Relative strength of the C-Hal bond b) explain the uses of fluoroalkanes and fluorohalogenoalkanes in terms of their relative chemical inertness c) recognise the concern about the effect of chlorofluoroalkanes on the ozone layer

LESSON OBJECTIVE: Explain the trends observed across the periodic table including atomic radius, ionic radius, melting point, electrical conductivity and first ionisation energy. In this lesson we discuss the concept of periodicity and justify the trends we observe in a number of physical properties as we move across the Period 3 elements. This is lesson one in our inorganic chemistry series for Unit 9: The Periodic Table: chemical periodicity (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 9.1 Periodicity of physical properties of the elements in Period 3 a) describe qualitatively (and indicate the periodicity in) the variations in atomic radius, ionic radius, melting point and electrical conductivity of the elements (see the Data Booklet) b) explain qualitatively the variation in atomic radius and ionic radius c) interpret the variation in melting point and electrical conductivity in terms of the presence of simple molecular, giant molecular or metallic bonding in the elements d) explain the variation in first ionisation energy (see the Data Booklet)

LESSON OBJECTIVE: Understand the properties of aldehydes and ketones as carbonyl compounds by investigating their synthesis and key chemical reactions. In this lesson we investigate the carbonyl compounds aldehydes and ketones by discussing their synthesis via the oxidation of alcohols, their reduction back to the corresponding alcohol and their nucleophilic addition reactions with cyanide. This is lesson twelve in our organic chemistry series of Unit 18: Carbonyl compounds (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 18.1 Aldehydes and ketones a) describe: i) the formation of aldehydes and ketones from primary and secondary alcohols respectively using Cr2O72-/H+ ii) the reduction of aldehydes and ketones, e.g. using NaBH4 or LiAlH4 iii) the reaction of aldehydes and ketones with HCN and NaCN or KCN b) describe the mechanism of the nucleophilic addition reactions of hydrogen cyanide with aldehydes and ketones

LESSON OBJECTIVE: Investigate carboxylic acids, understand their characteristic reactions and describe the acid/base hydrolysis of esters. In this lesson we introduce the homologous series of carboxylic acids, their synthesis and a number of reactions including reduction, esterification and their reactions as an acid. This is lesson fourteen in our organic chemistry series of Unit 19: Carboxylic acids and derivatives (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 19.1 Carboxylic acids a) describe the formation of carboxylic acids from alcohols, aldehydes and nitriles b) describe the reactions of carboxylic acids in the formation of: (i) salts, by the use of reactive metals, alkalis or carbonates (ii) alkyl esters (iii) alcohols, by the use of LiAlH4 19.3 Esters a) describe the acid and base hydrolysis of esters b) state the major commercial uses of esters, e.g. solvent, perfumes and flavourings

In this lesson we discuss the concept of using oxidation states to determine whether a species has been reduced or oxidised, introduce the idea of oxidising and reducing agents, how to use oxidation for naming conventions and how to use oxidation numbers to balance redox reactions. This is lesson nineteen in our physical chemistry series for Unit 6: Electrochemistry (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Use oxidation numbers to determine oxidising and reducing agents, understand naming conventions and to balance chemical equations. LEARNING OUTCOMES (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum): 6.1 Redox processes: electron transfer and changes in oxidation number (oxidation state) c) use changes in oxidation numbers to help balance chemical equations

LESSON OBJECTIVE: Understand the periodicity of the Period 3 chlorides and for other elements in the Periodic Table In this lesson we investigate the periodicity observed in the Period 3 chlorides and extrapolate our understanding of periodicity to other elements beyond just Period 3 in the Periodic Table. This is lesson three in our inorganic chemistry series for Unit 9: The Periodic Table: chemical periodicity (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 9.2 Periodicity of chemical properties of the elements in Period 3 a) describe the reactions, if any, of the elements with oxygen (to give Na2O, MgO, Al2O3, P4O10, SO2, SO3), chlorine (to give NaCl, MgCl2, Al2Cl6, SiCl4, PCl5) and water (Na and Mg only) b) state and explain the variation in oxidation number of the oxides (sodium to sulfur only) and chlorides (sodium to phosphorus only) in terms of their outer shell (valence shell) electrons e) describe and explain the reactions of the chlorides with water f) interpret the variations and trends in 9.2(b), ©, (d) and (e) in terms of bonding and electronegativity g) suggest the types of chemical bonding present in chlorides and oxides from observations of their chemical and physical properties 9.3 Chemical periodicity of other elements a) predict the characteristic properties of an element in a given group by using knowledge of chemical periodicity b) deduce the nature, possible position in the Periodic Table and identify of unknown elements from given information about physical and chemical properties

LESSON OBJECTIVE: Understand and describe the trends in the physical and chemical properties of the Group 2 Metals. In this lesson we investigate the trends observed in the Group 2 metals physical properties, including atomic radius, melting point and density, and begin to discuss the properties in their chemical properties. This is lesson four in our inorganic chemistry series for Unit 10: Group 2 (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 10.1 Similarities and trends in the properties of the Group 2 metals, magnesium to barium, and their compounds a) describe the reactions of the elements with oxygen, water and dilute acids b) describe the behaviour of the oxides, hydroxides and carbonates with water and dilute acids d) interpret, and make predictions from, the trends in physical and chemical properties of the elements and their compounds

LESSON OBJECTIVE: Describe chemical tests that can be used to test for, and distinguishing between, the carbonyls present in aldehydes and ketones In this lesson we describe the 2,4-DNPH test to identify the carbonyl on an aldehyde or ketones and then investigates tests using Fehling’s and Tollens’ reagent to distinguish between the two. Finally we discuss the iodoform test to identify a methyl ketone group present. This is lesson thirteen in our organic chemistry series of Unit 18: Carbonyl compounds (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 18.1 Aldehydes and ketones c) describe the use of 2,4-dinitrophenylhydrazine (2,4-DNPH) to detect the presence of carbonyl compounds d) deduce the nature (aldehyde or ketone) of an unknown carbonyl compound from the results of simple tests (Fehling’s and Tollens’ reagents; ease of oxidation) e) describe the reaction of CH3CO- compounds with alkaline aqueous iodine to give tri-iodomethane

In this lesson we focus on the rules stating how electrons fill orbitals and how to write electron subshell configuration. This is lesson six in our physical chemistry series for Unit 2: Atomic Structure (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Understand how electrons fill orbitals and to determine subshell electronic configuration for given atoms and ions. LEARNING OUTCOMES (from the Cambridge AS Chemistry Curriculum 2019-2021): 2.3 Electrons: energy levels, atomic orbitals, ionisation energy, electron affinity c) state the electronic configuration of atoms and ions given the proton (atomic) number and charge, using the convention 1s22s22p6, etc.

In this lesson we introduce the concept of reaction kinetics focusing on collision theory, rates of reaction, activation energy and the effect that changing concentration and pressure will have on reaction rates. This is lesson twenty four in our physical chemistry series for Unit 8: Reaction kinetics (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Define rate of reactions in terms of collision theory and activation energy and understand the effect concentration has on reaction rates. LEARNING OUTCOMES (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum): 8.1 Simple Rate Equations, Orders of Reaction and Rate Constants a) explain and use the term rate of reaction b) explain qualitatively, in terms of collisions, the effect of concentration changes on the rate of reaction

LESSON OBJECTIVE: Investigate certain properties of hydrocarbons, understand the extraction of alkanes from crude oil via fractional distillation and describe the uses and pollutions of hydrocarbon combustion. In this lesson we discuss how crude oil can be separated using fractional distillation into different fractions for various uses, how combustion reactions of hydrocarbons allow them to be used as fuels and the effects of the pollution that arises from this and discuss the effects on the solubility of molecules. This is lesson five in our organic chemistry series of Unit 15: Hydrocarbons (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). Learning Outcomes: (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum) 15.1 Alkanes d) explain the use of crude oil as a source of both aliphatic and aromatic hydrocarbons e) suggest how cracking can be used to obtain more useful alkanes and alkenes of lower Mr from larger hydrocarbon molecules 15.3 Hydrocarbons as fuels a) describe and explain how the combustion reactions of alkanes make them suitable to be used as fuels in industry, in the home and in transport b) recognise the environmental consequences of: (i) carbon monoxide, oxides of nitrogen and unburnt hydrocarbons arising from the internal combustion engine and of their catalytic removal (ii) gases that contribute to the enhanced greenhouse effect c) outline the use of infra-red spectroscopy in monitoring air pollution

This lesson goes over the concepts of empirical and molecular formulas and how to correctly use significant figures. This is lesson two in our physical chemistry series from unit 1: Atoms, Molecules and Stoichiometry (from the Cambridge International AS Chemistry Curriculum). LESSON OBJECTIVE: Understand and calculate empirical and molecular formulas. Understand how to report calculations to the correct amount of significant figures. LEARNING OUTCOMES (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum): 1.4 The calculation of empirical and molecular formulae a) define and use the terms empirical and molecular formula b) calculate empirical and molecular formulae, using combustion data or composition by mass

In this lesson we describe the relationship between temperature and reaction rates and introduce the concept of the Boltzmann distribution. This is lesson twenty five in our physical chemistry series for Unit 8: Reaction kinetics (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Describe the effect of temperature on reaction rates and illustrate this on a Boltzmann distribution. LEARNING OUTCOMES (taken from the Cambridge International AS and A Level Chemistry (9701) 2019-2021 curriculum): 8.2 Effect of temperature: on reaction rates and rate constants and the concept of activation energy a) explain and use the term activation energy, including reference to the Boltzmann distribution b) explain qualitatively, in terms both of the Boltzmann distribution and of collision frequency, the effect of temperature change on the rate of a reaction

In this lesson we go over the subatomic particles in the atom and the concept of the nucleus. This is lesson four in our physical chemistry series for Unit 2: Atomic Structure (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Understand the properties of subatomic particles of an element including naming, mass and charge conventions for elements and isotopes. LEARNING OUTCOMES (from the Cambridge AS Chemistry Curriculum 2019-2021): 2.1 Particles in the atom a) identify and describe protons, neutrons and electrons in terms of their relative charges and relative masses b) deduce the behaviour of beams of protons, neutrons and electrons in electric fields c) describe the distribution of mass and charge within an atom d) deduce the numbers of protons, neutrons and electrons present in both atoms and ions given proton and nucleon numbers (atomic and mass numbers) and charge 2.2 The nucleus of the atom a) describe the contribution of protons and neutrons to atomic nuclei in terms of proton (atomic) number and nucleon (mass) number b) distinguish between isotopes on the basis of different numbers of neutrons present c) recognise and use the symbolism xyA for isotopes, where x is the nucleon (mass) number and y is the proton (atomic) number

In this lesson we discuss the relative strength of intermolecular forces and how different types of chemical bonding will affect a species physical properties. This is lesson eleven in our physical chemistry series for Unit 3: Chemical Bonding (from the Cambridge International AS Chemistry Curriculum (9701) 2019-2021 curriculum). LESSON OBJECTIVE: Identify and rationalise the types of intermolecular forces a molecule will have and consequently describe and predict the physical properties of different species based on the type of bonding present. Learning Outcomes (from the Cambridge AS Chemistry Curriculum 2019-2021): 3.5 Bonding and physical properties a) describe, interpret and predict the effect of different types of bonding (ionic bonding, covalent bonding, hydrogen bonding, other intermolecular interactions, metallic bonding) on the physical properties of substances b) deduce the type of bonding present from given information c) show understanding of chemical reactions in terms of energy transfers associated with the breaking and making of chemical bonds