Unit 2: Energetics, Group Chemistry, Halogenoalkanes and Alcohols
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Topic 6: Energetics
6.1The enthalpy change, ∆H, is the heat energy change measured at constant pressure and that standard conditions are 100 kPa
Know that the enthalpy change, ∆H, is the heat energy change measured at constant pressure and that standard conditions are 100 kPa and a specified temperature, usually 298 K
6.2That, by convention, exothermic reactions have a negative enthalpy change and endothermic reactions have a positive enthalpy
Know that, by convention, exothermic reactions have a negative enthalpy change and endothermic reactions have a positive enthalpy change
6.3Construct and interpret enthalpy level diagrams, showing exothermic and endothermic enthalpy changes
Be able to construct and interpret enthalpy level diagrams, showing exothermic and endothermic enthalpy changes
6.4The definition of standard enthalpy change of: i reaction, ∆rH ii formation, ∆fH iii combustion, ∆cH iv neutralisation
Know the definition of standard enthalpy change of: i reaction, ∆rH ii formation, ∆fH iii combustion, ∆cH iv neutralisation, ∆neutH v atomisation, ∆atH
6.5Experimental data to calculate: i energy transferred in a reaction recalling and using the expression: energy transferred
Be able to use experimental data to calculate: i energy transferred in a reaction recalling and using the expression: energy transferred (J) = mass (g) × specific heat capacity (J g-1 °C-1) × temperature change (°C) ii enthalpy change of the reaction in kJ mol⁻¹ This will be limited to experiments where substances are mixed in an insulated container and combustion experiments using a suitable calorimeter.
6.6Hess’s Law
Know Hess’s Law and be able to apply it to: i constructing enthalpy cycles ii calculating enthalpy changes of reaction using data provided, or data selected from a table or obtained from experiments
6.7CORE PRACTICAL 2 Determination of the enthalpy change of a reaction using Hess’s Law
CORE PRACTICAL 2 Determination of the enthalpy change of a reaction using Hess’s Law.
6.8Evaluate the results obtained from experiments and comment on sources of error and uncertainty and any assumptions made
Be able to evaluate the results obtained from experiments and comment on sources of error and uncertainty and any assumptions made in the experiments Students will need to consider experiments where substances are mixed in an insulated container and combustion experiments using, for example, a spirit burner and be able to draw suitable graphs and use cooling curve corrections.
6.9The terms ‘bond enthalpy’ and ‘mean bond enthalpy’
Understand the terms ‘bond enthalpy’ and ‘mean bond enthalpy’, and be able to use bond enthalpies to calculate enthalpy changes, understanding the limitations of this method
6.10Mean bond enthalpies from enthalpy changes of reaction
Be able to calculate mean bond enthalpies from enthalpy changes of reaction
6.11Bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is
Understand that bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is and therefore how rapidly a reaction will take place at room temperature
Topic 7: Intermolecular Forces
7.1The nature of the following intermolecular forces: i London forces (instantaneous dipole-induced dipole) ii permanent
Understand the nature of the following intermolecular forces: i London forces (instantaneous dipole-induced dipole) ii permanent dipole-permanent dipole interactions iii hydrogen bonds
7.2The interactions in molecules, such as H2O, liquid NH3 and liquid HF, which give rise to hydrogen bonding
Understand the interactions in molecules, such as H2O, liquid NH3 and liquid HF, which give rise to hydrogen bonding
7.3The following anomalous properties of water resulting from hydrogen bonding: i its high melting and boiling temperature when
Understand the following anomalous properties of water resulting from hydrogen bonding: i its high melting and boiling temperature when compared with similar molecules ii the density of ice compared to that of water
7.4Predict the presence of hydrogen bonding in molecules analogous to those mentioned in 7.2
Be able to predict the presence of hydrogen bonding in molecules analogous to those mentioned in 7.2
7.5Understand, in terms of intermolecular forces, physical properties shown by substances
Understand, in terms of intermolecular forces, physical properties shown by substances, including: i the trends in boiling temperatures of alkanes with increasing chain length ii the effect of branching in the carbon chain on the boiling temperatures of alkanes iii the relatively low volatility (higher boiling temperatures) of alcohols compared to alkanes with a similar number of electrons iv the trends in boiling temperatures of the hydrogen halides HF to HI
7.6Factors that influence the choice of solvents
Understand factors that influence the choice of solvents, including: i water, to dissolve some ionic compounds, in terms of the hydration of the ions ii water, to dissolve simple alcohols, in terms of hydrogen bonding iii water, as a poor solvent for compounds (to include polar molecules such as halogenoalkane), in terms of inability to form hydrogen bonds iv non-aqueous solvents, for compounds that have similar intermolecular forces to those in the solvent
Topic 8: Redox Chemistry and Groups 1, 2 and 7
8.1What is meant by the term ‘oxidation number’ and understand the rules for assigning oxidation numbers
Know what is meant by the term ‘oxidation number’ and understand the rules for assigning oxidation numbers
8.2The oxidation number of elements in compounds and ions
Be able to calculate the oxidation number of elements in compounds and ions, including in peroxides and metal hydrides
8.3Indicate the oxidation number of an element in a compound or an ion
Be able to indicate the oxidation number of an element in a compound or an ion, using a Roman numeral
8.4Write formulae given oxidation numbers
Be able to write formulae given oxidation numbers
8.5Oxidation and reduction in terms of electron transfer and changes in oxidation number, and the application of these ideas
Understand oxidation and reduction in terms of electron transfer and changes in oxidation number, and the application of these ideas to reactions of s-block and p-block elements
8.6Oxidising agents gain electrons and reducing agents lose electrons
Know that oxidising agents gain electrons and reducing agents lose electrons
8.7A disproportionation reaction involves an element in a single species being simultaneously oxidised and reduced
Understand that a disproportionation reaction involves an element in a single species being simultaneously oxidised and reduced
8.8Oxidation number is a useful concept in terms of the classification of reactions as redox and as disproportionation
Know that oxidation number is a useful concept in terms of the classification of reactions as redox and as disproportionation
8.9Metals, in general, form positive ions by loss of electrons with an increase in oxidation number whereas non-metals
Understand that metals, in general, form positive ions by loss of electrons with an increase in oxidation number whereas non-metals, in general, form negative ions by gain of electrons with a decrease in oxidation number
8.10Write ionic half-equations and use them to construct full ionic equations 8B: The elements of Groups 1 and 2 Students will
Be able to write ionic half-equations and use them to construct full ionic equations 8B: The elements of Groups 1 and 2 Students will be assessed on their ability to:
8.11Reasons for the trend in ionisation energy down Groups 1 and 2
Understand reasons for the trend in ionisation energy down Groups 1 and 2
8.12Reasons for the trend in reactivity of the elements down Group 1 (Li to K) and Group 2 (Mg to Ba)
Understand reasons for the trend in reactivity of the elements down Group 1 (Li to K) and Group 2 (Mg to Ba)
8.13The reactions of the elements of Group 1 (Li to K) and Group 2 (Mg to Ba) with oxygen, chlorine and water
Know the reactions of the elements of Group 1 (Li to K) and Group 2 (Mg to Ba) with oxygen, chlorine and water
8.14The reactions of: i oxides of Group 1 and 2 elements with water and dilute acid ii hydroxides of Group 1 and 2 elements
Know the reactions of: i oxides of Group 1 and 2 elements with water and dilute acid ii hydroxides of Group 1 and 2 elements with dilute acid
8.15The trends in solubility of the hydroxides and sulfates of Group 2 elements
Know the trends in solubility of the hydroxides and sulfates of Group 2 elements
8.16The reasons for the trends in thermal stability of the nitrates and the carbonates of the elements in Groups 1 and 2
Understand the reasons for the trends in thermal stability of the nitrates and the carbonates of the elements in Groups 1 and 2 in terms of the size and charge of the cations involved
8.17The formation of characteristic flame colours by Group 1 and 2 compounds in terms of electron transitions Students will be
Understand the formation of characteristic flame colours by Group 1 and 2 compounds in terms of electron transitions Students will be expected to know the flame colours for Group 1 and 2 compounds.
8.18Experimental procedures to show: i patterns in the thermal decomposition of Group 1 and 2 nitrates and carbonates Students
Know experimental procedures to show: i patterns in the thermal decomposition of Group 1 and 2 nitrates and carbonates Students will be expected to know tests for carbon dioxide and oxygen; and to recognise nitrogen dioxide by its colour and acidic pH. ii flame colours in compounds of Group 1 and 2 elements
8.19Reactions
Know reactions, including ionic equations where appropriate, for identifying: (i) carbonate ions, CO3^2−, and hydrogencarbonate ions, HCO3−, using aqueous acid to form carbon dioxide and limewater to test the gas; (ii) sulfate ions, SO4^2−, using acidified barium chloride solution; and (iii) ammonium ions, NH4+, using sodium hydroxide solution and warming to form ammonia, tested with litmus and HCl fumes.
8.20Solution concentrations, in mol dm-3 and g dm-3
Be able to calculate solution concentrations, in mol dm-3 and g dm-3, including simple acid-base titrations using the indicators methyl orange and phenolphthalein
8.21CORE PRACTICAL 3 Finding the concentration of a solution of hydrochloric acid
CORE PRACTICAL 3 Finding the concentration of a solution of hydrochloric acid.
8.22How to minimise the sources of measurement uncertainty in volumetric analysis and estimate the overall uncertainty in
Understand how to minimise the sources of measurement uncertainty in volumetric analysis and estimate the overall uncertainty in the calculated result
8.23CORE PRACTICAL 4 Preparation of a standard solution from a solid acid and use it to find the concentration of a solution
CORE PRACTICAL 4 Preparation of a standard solution from a solid acid and use it to find the concentration of a solution of sodium hydroxide.
8.24Reasons for the trends for Group 7 elements in: i melting and boiling temperatures and physical state at room temperature ii
Understand reasons for the trends for Group 7 elements in: i melting and boiling temperatures and physical state at room temperature ii electronegativity iii reactivity down the group
8.25The trend in reactivity of Group 7 elements in terms of the redox reactions of Cl2, Br2 and I2 with halide ions in aqueous
Understand the trend in reactivity of Group 7 elements in terms of the redox reactions of Cl2, Br2 and I2 with halide ions in aqueous solution Students are expected to know the colours of the elements in standard conditions, in aqueous solution and in a non-polar organic solvent.
8.26Understand, in terms of changes in oxidation number, the following reactions of the halogens: i oxidation reactions
Understand, in terms of changes in oxidation number, the following reactions of the halogens: i oxidation reactions with Group 1 and 2 metals ii the disproportionation reaction of chlorine with water and the use of chlorine in water treatment iii the disproportionation reaction of chlorine with cold, dilute aqueous sodium hydroxide to form bleach iv the disproportionation reaction of chlorine with hot alkali v reactions analogous to those specified above
8.27The following reactions: i solid Group 1 halides with concentrated sulfuric acid, to illustrate the trend in reducing
Understand the following reactions: i solid Group 1 halides with concentrated sulfuric acid, to illustrate the trend in reducing ability of the hydrogen halides ii precipitation reactions of the aqueous anions Cl-, Br- and I- with aqueous silver nitrate solution and nitric acid, and the solubility of the precipitates in aqueous ammonia solution iii hydrogen halides with ammonia gas (to produce ammonium halides) and with water (to produce acids)
8.28Make predictions about fluorine and astatine and their compounds, in terms of knowledge of trends in halogen chemistry
Be able to make predictions about fluorine and astatine and their compounds, in terms of knowledge of trends in halogen chemistry
Topic 9: Introduction to Kinetics and Equilibria
9.1Understand, in terms of the collision theory, the effect of changes in concentration, temperature, pressure and surface area
Understand, in terms of the collision theory, the effect of changes in concentration, temperature, pressure and surface area on the rate of a chemical reaction
9.2Reactions take place only when collisions have sufficient energy, known as the activation energy
Understand that reactions take place only when collisions have sufficient energy, known as the activation energy
9.3The rate of a reaction from: i the time taken for a reaction
Be able to calculate the rate of a reaction from: i the time taken for a reaction, using rate = 1/time ii the gradient of suitable graph, by drawing a tangent, either for initial rate, or at a time, t
9.4Qualitatively, in terms of the Maxwell-Boltzmann distribution of molecular energies, how changes in temperature affect
Understand qualitatively, in terms of the Maxwell-Boltzmann distribution of molecular energies, how changes in temperature affect the rate of a reaction
9.5The role of catalysts in providing alternative reaction routes of lower activation energy
Understand the role of catalysts in providing alternative reaction routes of lower activation energy
9.6Draw the reaction profiles for uncatalysed and catalysed reactions
Be able to draw the reaction profiles for uncatalysed and catalysed reactions, including the energy level of the intermediate formed with the catalyst
9.7The use of catalysts in industry to make processes more sustainable by using less energy and/or higher atom economy
Understand the use of catalysts in industry to make processes more sustainable by using less energy and/or higher atom economy
9.8Interpret the action of a catalyst in terms of a qualitative understanding of the Maxwell-Boltzmann distribution
Be able to interpret the action of a catalyst in terms of a qualitative understanding of the Maxwell-Boltzmann distribution of molecular energies
9.9Many reactions are readily reversible and that they can reach a state of dynamic equilibrium in which: i the rate of
Know that many reactions are readily reversible and that they can reach a state of dynamic equilibrium in which: i the rate of the forward reaction is equal to the rate of the backward reaction ii the concentrations of the reactants and the products remain constant
9.10Predict and justify the qualitative effects of changes of temperature, pressure and concentration on the position
Be able to predict and justify the qualitative effects of changes of temperature, pressure and concentration on the position of equilibrium in a homogeneous system
9.11Evaluate data to explain the necessity, for many industrial processes, to reach a compromise between the yield and the rate
Evaluate data to explain the necessity, for many industrial processes, to reach a compromise between the yield and the rate of reaction
Topic 10: Organic Chemistry: Halogenoalkanes, Alcohols and Spectra
10.1Classify reactions (including those in Unit 1) as addition, elimination, substitution, oxidation, reduction, hydrolysis or
Be able to classify reactions (including those in Unit 1) as addition, elimination, substitution, oxidation, reduction, hydrolysis or polymerisation
10.2The concept of a reaction mechanism
Understand the concept of a reaction mechanism
10.3Heterolytic bond breaking results in species that are electrophiles or nucleophiles
Understand that heterolytic bond breaking results in species that are electrophiles or nucleophiles
10.4The definition of the term ‘nucleophile’
Know the definition of the term ‘nucleophile’
10.5The link between bond polarity and the type of reaction mechanism a compound will undergo 10B: Halogenoalkanes Students will
Understand the link between bond polarity and the type of reaction mechanism a compound will undergo 10B: Halogenoalkanes Students will be assessed on their ability to:
10.6The nomenclature of halogenoalkanes
Understand the nomenclature of halogenoalkanes and be able to draw their structural, displayed and skeletal formulae
10.7The distinction between primary, secondary and tertiary halogenoalkanes
Understand the distinction between primary, secondary and tertiary halogenoalkanes
10.8The reactions of halogenoalkanes with: i aqueous alkali
Understand the reactions of halogenoalkanes with: i aqueous alkali, including KOH(aq) to produce alcohols (where the hydroxide ion acts as a nucleophile) ii ethanolic potassium hydroxide to produce alkenes by an elimination reaction (where the hydroxide ion acts as a base) iii aqueous silver nitrate in ethanol (where water acts as a nucleophile) iv alcoholic ammonia under pressure to produce amines (where the ammonia acts as a nucleophile) v alcoholic potassium cyanide to produce nitriles (where the cyanide ion acts as a nucleophile) Students should know this is an example of increasing the length of the carbon chain.
10.9The mechanisms of the nucleophilic substitution reactions between primary halogenoalkanes and: i aqueous potassium hydroxide
Understand the mechanisms of the nucleophilic substitution reactions between primary halogenoalkanes and: i aqueous potassium hydroxide ii ammonia SN1 and SN2 substitution mechanisms will be tested in Unit 4.
10.10Experimental observations and data can be used to compare the relative rates of hydrolysis of: i primary, secondary
Understand that experimental observations and data can be used to compare the relative rates of hydrolysis of: i primary, secondary and tertiary structural isomers of a halogenoalkane ii primary chloro-, bromo- and iodoalkanes using aqueous silver nitrate in ethanol
10.11CORE PRACTICAL 5 Investigation of the rates of hydrolysis of some halogenoalkanes
CORE PRACTICAL 5 Investigation of the rates of hydrolysis of some halogenoalkanes.
10.12The trend in reactivity of primary, secondary and tertiary halogenoalkanes
Know the trend in reactivity of primary, secondary and tertiary halogenoalkanes
10.13Understand, in terms of bond enthalpy, the trend in reactivity of chloro-, bromo- and iodoalkanes
Understand, in terms of bond enthalpy, the trend in reactivity of chloro-, bromo- and iodoalkanes
10.14CORE PRACTICAL 6 Chlorination of 2-methylpropan-2-ol with concentrated hydrochloric acid
CORE PRACTICAL 6 Chlorination of 2-methylpropan-2-ol with concentrated hydrochloric acid.
10.15The nomenclature of alcohols
Understand the nomenclature of alcohols and be able to draw their structural, displayed and skeletal formulae
10.16The distinction between primary, secondary and tertiary alcohols
Understand the distinction between primary, secondary and tertiary alcohols
10.17The reactions of alcohols with: i oxygen in air (combustion) ii halogenating agents • PCl5 to produce chloroalkanes
Understand the reactions of alcohols with: i oxygen in air (combustion) ii halogenating agents • PCl5 to produce chloroalkanes (including its use as a qualitative test for the presence of the –OH group) • 50% concentrated sulfuric acid and potassium bromide to produce bromoalkanes • red phosphorus and iodine to produce iodoalkanes iii concentrated phosphoric acid to form alkenes by elimination Descriptions of the mechanisms of these reactions are not required.
10.18Potassium dichromate(VI) in dilute sulfuric acid can oxidise: i primary alcohols to produce aldehydes (which give a positive
Understand that potassium dichromate(VI) in dilute sulfuric acid can oxidise: i primary alcohols to produce aldehydes (which give a positive result with Benedict’s or Fehling’s solution) if the product is distilled as it forms ii primary alcohols to produce carboxylic acids (which give a positive result with sodium carbonate or sodium hydrogencarbonate) if the reagents are heated under reflux iii secondary alcohols to produce ketones In equations, the oxidising agent can be represented by [O].
10.19Understand, the following techniques in the preparation and purification of a liquid organic compound: i heating under
Understand, the following techniques in the preparation and purification of a liquid organic compound: i heating under reflux ii extraction with a solvent using a separating funnel iii distillation iv drying with an anhydrous salt v boiling temperature determination
10.20CORE PRACTICAL 7 The oxidation of propan-1-ol to produce propanal and propanoic acid
CORE PRACTICAL 7 The oxidation of propan-1-ol to produce propanal and propanoic acid.
10.21Interpret data from mass spectra to suggest possible structures of simple organic compounds using the m/z of the molecular
Be able to interpret data from mass spectra to suggest possible structures of simple organic compounds using the m/z of the molecular ion and fragmentation patterns
10.22Infrared spectra, or data from infrared spectra, to deduce functional groups present in organic compounds, and predict
Be able to use infrared spectra, or data from infrared spectra, to deduce functional groups present in organic compounds, and predict infrared absorptions, given wavenumber data, due to familiar functional groups including: i C–H stretching absorptions in alkanes, alkenes and aldehydes ii C=C stretching absorption in alkenes iii O–H stretching absorptions in alcohols and carboxylic acids iv C=O stretching absorptions in aldehydes, ketones and carboxylic acids v C–X stretching absorption in halogenoalkanes vi N-H stretching absorption in amines
10.23CORE PRACTICAL 8 Analysis of some inorganic and organic unknowns
CORE PRACTICAL 8 Analysis of some inorganic and organic unknowns.