Unit 1: Structure, Bonding and Introduction to Organic Chemistry

1.1The terms ‘atom', 'element', 'ion', 'molecule', 'compound', 'empirical formula' and 'molecular formula’

Know the terms ‘atom', 'element', 'ion', 'molecule', 'compound', 'empirical formula' and 'molecular formula’

1.2The mole (mol) is the unit for the amount of a substance

Know that the mole (mol) is the unit for the amount of a substance and be able to perform calculations using the Avogadro constant L (6.02 × 10²³ mol⁻¹)

1.3Write balanced full and ionic equations

Write balanced full and ionic equations, including state symbols, for chemical reactions

1.4The terms: i ‘relative atomic mass’ based on the 12C scale ii ‘relative molecular mass’ and ‘relative formula mass’

Understand the terms: i ‘relative atomic mass’ based on the 12C scale ii ‘relative molecular mass’ and ‘relative formula mass’, including calculating these values from relative atomic masses The term ‘relative formula mass’ should be used for compounds with giant structures. iii ‘molar mass’ as the mass per mole of a substance in g mol⁻¹ iv parts per million (ppm), including gases in the atmosphere

1.5The concentration of a solution in mol dm−3 and g dm−3 Titration calculations are not required at this stage

Calculate the concentration of a solution in mol dm−3 and g dm−3 Titration calculations are not required at this stage.

1.6Experimental data to calculate empirical and molecular formulae

Be able to use experimental data to calculate empirical and molecular formulae

1.7Chemical equations to calculate reacting masses and vice versa

Be able to use chemical equations to calculate reacting masses and vice versa, using the concepts of amount of substance and molar mass

1.8Chemical equations to calculate volumes of gases and vice versa

Be able to use chemical equations to calculate volumes of gases and vice versa, using: i the concepts of amount of substance ii the molar volume of gases iii the expression pV = nRT for gases and volatile liquids

1.9Percentage yields and percentage atom economies (by mass) in laboratory and industrial processes

Be able to calculate percentage yields and percentage atom economies (by mass) in laboratory and industrial processes, using chemical equations and experimental results Atom economy = molar mass of the desired product × 100% sum of the molar masses of all products

1.10Determine a formula or confirm an equation by experiment

Be able to determine a formula or confirm an equation by experiment, including evaluation of the data

1.11CORE PRACTICAL 1 Measurement of the molar volume of a gas

CORE PRACTICAL 1 Measurement of the molar volume of a gas.

1.12Relate ionic and full equations, with state symbols, to observations from simple test-tube experiments, to include: i

Be able to relate ionic and full equations, with state symbols, to observations from simple test-tube experiments, to include: i displacement reactions ii typical reactions of acids iii precipitation reactions

Know the structure of an atom in terms of electrons, protons and neutrons

Know the relative mass and charge of protons, neutrons and electrons

Know what is meant by the terms ‘atomic (proton) number’ and ‘mass number’

Be able to use the atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion

Understand the term ‘isotope’

Understand the basic principles of a mass spectrometer and be able to analyse and interpret mass spectra to: i deduce the isotopic composition of a sample of an element ii calculate the relative atomic mass of an element from relative abundances of isotopes and vice versa iii determine the relative molecular mass of a molecule, and hence identify molecules in a sample iv understand that ions in a mass spectrometer may have a 2+ charge

Be able to predict mass spectra, including relative peak heights, for diatomic molecules, including chlorine, given the isotopic abundances

Be able to define first, second and third ionisation energies and understand that all ionisation energies are endothermic

Know that an orbital is a region within an atom that can hold up to two electrons with opposite spins

Understand how ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell from which the electron is removed

Know that ideas about electronic structure developed from: i an understanding that successive ionisation energies provide evidence for the existence of quantum shells and the group to which the element belongs ii an understanding that the first ionisation energy of successive elements provides evidence for electron sub-shells

Be able to describe the shapes of s and p orbitals

Know that orbitals in sub-shells: i each take a single electron before pairing up ii pair up with two electrons of opposite spin

Be able to predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions, using s, p, d notation and electron-in- boxes notation

Understand that electronic configuration determines the chemical properties of an element

Know that the Periodic Table is divided into blocks, such as s, p and d, and know the number of electrons that can occupy s, p and d sub-shells in the first four quantum shells

Be able to represent data, in a graphical form (including the use of logarithms of first ionisation energies on a graph) for elements 1 to 36 and hence explain the meaning of the term ‘periodic property’

Be able to explain: i the trends in melting and boiling temperatures of the elements of Periods 2 and 3 of the Periodic Table in terms of the structure of the element and the bonding between its atoms or molecules ii the general increase and the specific trends in ionisation energy of the elements across Periods 2 and 3 of the Periodic Table iii the decrease in first ionisation energy down a group

Know and be able to interpret evidence for the existence of ions, limited to physical properties of ionic compounds, electron density maps and the migration of ions

Be able to describe the formation of ions in terms of loss or gain of electrons

Be able to draw dot-and-cross diagrams to show electrons in cations and anions

Be able to describe ionic crystals as giant lattices of ions

Know that ionic bonding is the result of strong net electrostatic attraction between ions

Understand the effects of ionic radius and ionic charge on the strength of ionic bonding

Understand reasons for the trends in ionic radii down a group in the Periodic Table, and for a set of isoelectronic ions, including N3− to Al3+

Understand the meaning of the term ‘polarisation’ as applied to ions

Understand that the polarising power of a cation depends on its radius and charge, and the polarisability of an anion also depends on its radius and charge

Understand that covalent bonding is the strong electrostatic attraction between two nuclei and the shared pair of electrons between them, based on the evidence: i the physical properties of giant atomic structures ii electron density maps for simple molecules

Be able to draw dot-and-cross diagrams to show electrons in covalent substances, including: i molecules with single, double and triple bonds ii species with dative covalent (coordinate) bonds, including Al2Cl6 and the ammonium ion

Be able to describe the different structures formed by giant lattices of carbon atoms, including graphite, diamond and graphene, and discuss the applications of each

Understand the meaning of the term ‘electronegativity’ as applied to atoms in a covalent bond

Know that ionic and covalent bonding are the extremes of a continuum of bonding type and be able to explain this in terms of electronegativity differences, leading to bond polarity in bonds and molecules, and to ionic bonding if the electronegativity is large enough

Be able to distinguish between polar bonds and polar molecules and predict whether or not a given molecule is likely to be polar

Understand the principles of the electron-pair repulsion theory, used to interpret and predict the shapes of simple molecules and ions

Understand the terms ‘bond length’ and ‘bond angle’

Know and explain the shapes of, and bond angles in, BeCl2, BCl3, CH4, NH3, NH4+, H2O, CO2, gaseous PCl5, SF6 and C2H4.

Be able to apply the electron-pair repulsion theory to predict the shapes of, and bond angles in, molecules and ions analogous to those in 3.18 3D: Metallic bonding Students will be assessed on their ability to:

Understand that metals consist of giant lattices of metal ions in a sea of delocalised electrons

Know that metallic bonding is the strong electrostatic attraction between metal ions and the delocalised electrons

Be able to use the models in 3.20 and 3.21 to interpret simple properties of metals, including electrical conductivity and high melting temperature

Understand the difference between hazard and risk

Understand the hazards associated with organic compounds and why it is necessary to carry out risk assessments when dealing with potentially hazardous materials

Be able to suggest ways in which risks can be reduced and reactions carried out safely, for example: i working on a smaller scale ii taking precautions specific to the hazard iii using an alternative method that involves less hazardous substances

Understand the concepts of homologous series and functional group

Be able to apply the rules of International Union of Pure and Applied Chemistry (IUPAC) nomenclature to: i name compounds relevant to this specification ii draw these compounds, as they are encountered in the specification, using structural, displayed and skeletal formulae Students will be expected to know prefixes for compounds up to C10

Be able to classify reactions as addition, substitution, oxidation, reduction or polymerisation

Understand that bond breaking can be: i homolytic, to produce free radicals ii heterolytic, to produce ions

Know definitions of the terms ‘free radical’ and ‘electrophile’ 4B: Alkanes Students will be assessed on their ability to:

Know the general formula of alkanes and cycloalkanes, and understand that they are hydrocarbons (compounds of carbon and hydrogen only) which are saturated (contain single bonds only)

Understand the term ‘structural isomerism’ and be able to draw the structural isomers of organic molecules, given their molecular formula

Be able to draw and name the structural isomers of alkanes and cycloalkanes with up to six carbon atoms

Know that alkanes are used as fuels and obtained from the fractional distillation, cracking and reforming of crude oil, and be able to write equations for these reactions

Know that pollutants, including carbon monoxide, oxides of nitrogen and sulfur, carbon particulates and unburned hydrocarbons, are emitted during the combustion of alkane fuels

Understand the problems arising from pollutants from the combustion of alkane fuels, limited to the toxicity of carbon monoxide and why it is toxic, and the acidity of oxides of nitrogen and sulfur

Be able to discuss the reasons for developing alternative fuels in terms of sustainability and reducing emissions, including the emission of CO2 and its relationship to climate change

Be able to apply the concept of carbon neutrality to different fuels, such as petrol, bioethanol and hydrogen

Understand the reactions of alkanes with: i oxygen in the air (combustion) ii halogens

Understand the mechanism of the free radical substitution reaction between an alkane and a halogen: i using free radicals, which are species with an unpaired electron, represented by a single dot ii showing the initiation step of the mechanism, with curly half-arrows for free radical formation iii showing the propagation and termination steps of the mechanism iv having limited use in synthesis because of further substitution reactions

Know the general formula of alkenes and understand that alkenes and cycloalkenes are hydrocarbons which are unsaturated (have a carbon-carbon double bond which consists of a σ bond and a π bond)

Be able to explain geometric isomerism in terms of restricted rotation around a C=C double bond and the nature of the substituents on the carbon atoms

Understand the E–Z naming system for geometric isomers and why it is necessary to use this when the cis- and trans- naming system breaks down

Be able to describe the reactions of alkenes, limited to: i the addition of hydrogen, using a nickel catalyst, to form an alkane ii the addition of halogens to produce a di-substituted halogenoalkane iii the addition of hydrogen halides to produce mono-substituted halogenoalkanes iv the addition of steam, in the presence of an acid catalyst, to produce alcohols v oxidation of the double bond by acidified potassium manganate(VII) to produce a diol

Know the qualitative test for a C=C double bond using bromine or bromine water

Be able to describe the mechanism (including diagrams), giving evidence where possible, of: i the electrophilic addition of bromine and hydrogen bromide to ethene ii the electrophilic addition of hydrogen bromide to propene Use of the curly arrow notation is expected – the curly arrows should start from either a bond or from a lone pair of electrons. Knowledge of the relative stability of primary, secondary and tertiary carbocation intermediates is expected.

Be able to describe the addition polymerisation of alkenes and draw the repeat unit given the monomer, and vice versa

Understand how chemists limit the problems caused by polymer disposal by: i developing biodegradable polymers ii removing toxic waste gases produced by the incineration of polymers