# Periodicity

graph LR Atom("Atomic structure") --> P0("Terminologies") ElecConf("Electron config") --> P0 G("General representations") --> PTr1("Atomic radii") Cov("Covalent bonding") --> PTr5("Electronegativity") Energetics("Enthalpy level diagrams / Exo/Endo") --> PTr2A subgraph 3 - Periodicity P0 --> PTr1 PTr1 --> PTr2A("Ionization energy basics") PTr2A --> PTr3("Ionic radii") PTr2A --> PTr4("Electron affinity") PTr3 --> PTr2C("IE - subshells") PTr2C --> PTr3D("IE - successive IE") PTr4 --> PTr5 end

# Terminologies

Arrangement by Z

Groups vs period

Numbering

Group names

Blocks & electronic configuration

Valence electrons

Need to know first 20 elements + halogens

# Atomic Radii

# Ionization energy

$\ce{X\gas{} -> X+\gas{} + e-}$

# Successive ionization energies


[ 2, 8, 8, 2 ]

[ 1 ]

[ 2, 8, 8, 2 ]

[ 1 ]
3.1.NoS Obtain evidence for scientific theories by making and testing predictions based on them—scientists organize subjects based on structure and function; the periodic table is a key example of this. Early models of the periodic table from Mendeleev, and later Moseley, allowed for the prediction of properties of elements that had not yet been discovered. (1.9)
3.1.U1 The periodic table is arranged into four blocks associated with the four sub- levels—s, p, d, and f.
3.1.U2 The periodic table consists of groups (vertical columns) and periods (horizontal rows).
3.1.U3 The period number (n) is the outer energy level that is occupied by electrons.
3.1.U4 The number of the principal energy level and the number of the valence electrons in an atom can be deduced from its position on the periodic table.
3.1.U5 The periodic table shows the positions of metals, non-metals and metalloids.
3.1.AS1 Deduction of the electron configuration of an atom from the element’s position on the periodic table, and vice versa.
3.1.G1 The terms alkali metals, halogens, noble gases, transition metals, lanthanoids and actinoids should be known.
3.1.G2 The group numbering scheme from group 1 to group 18, as recommended by IUPAC, should be used.
3.1.IM1 The development of the periodic table took many years and involved scientists from different countries building upon the foundations of each other’s work and ideas.
3.1.ToK1 What role did inductive and deductive reasoning play in the development of the periodic table? What role does inductive and deductive reasoning have in science in general?
3.1.Uz1 Other scientific subjects also use the periodic table to understand the structure and reactivity of elements as it applies to their own disciplines.
3.1.Aims1 Aim 3: Apply the organization of the periodic table to understand general trends in properties.
3.1.Aims2 Aim 4: Be able to analyse data to explain the organization of the elements.
3.1.Aims3 Aim 6: Be able to recognize physical samples or images of common elements.
3.2.NoS Looking for patterns—the position of an element in the periodic table allows scientists to make accurate predictions of its physical and chemical properties. This gives scientists the ability to synthesize new substances based on the expected reactivity of elements. (3.1)
3.2.U1 Vertical and horizontal trends in the periodic table exist for atomic radius, ionic radius, ionization energy, electron affinity and electronegativity.
3.2.U2 Trends in metallic and non-metallic behaviour are due to the trends above.
3.2.U3 Oxides change from basic through amphoteric to acidic across a period.
3.2.AS1 Prediction and explanation of the metallic and non-metallic behaviour of an element based on its position in the periodic table.
3.2.AS2 Discussion of the similarities and differences in the properties of elements in the same group, with reference to alkali metals (group 1) and halogens (group 17).
3.2.AS3 Construction of equations to explain the pH changes for reactions of Na2O, MgO, P4O10, and the oxides of nitrogen and sulfur with water.
3.2.G1 Only examples of general trends across periods and down groups are required. For ionization energy the discontinuities in the increase across a period should be covered.
3.2.G2 Group trends should include the treatment of the reactions of alkali metals with water, alkali metals with halogens and halogens with halide ions.
3.2.IM1 Industrialization has led to the production of many products that cause global problems when released into the environment.
3.2.ToK1 The predictive power of Mendeleev’s Periodic Table illustrates the “risk-taking” nature of science. What is the demarcation between scientific and pseudoscientific claims?
3.2.ToK2 The Periodic Table is an excellent example of classification in science. How does classification and categorization help and hinder the pursuit of knowledge?
3.2.Aims1 Aims 1 and 8: What is the global impact of acid deposition?
3.2.Aims2 Aim 6: Experiment with chemical trends directly in the laboratory or through the use of teacher demonstrations.
3.2.Aims3 Aim 6: The use of transition metal ions as catalysts could be investigated.
3.2.Aims4 Aim 7: Periodic trends can be studied with the use of computer databases.
13.1.NoS Looking for trends and discrepancies—transition elements follow certain patterns of behaviour. The elements Zn, Cr and Cu do not follow these patterns and are therefore considered anomalous in the first-row d-block.(3.1)
13.1.U1 Transition elements have variable oxidation states, form complex ions with ligands, have coloured compounds, and display catalytic and magnetic properties.
13.1.U2 Zn is not considered to be a transition element as it does not form ions with incomplete d-orbitals.
13.1.U3 Transition elements show an oxidation state of +2 when the s-electrons are removed.
13.1.AS1 Explanation of the ability of transition metals to form variable oxidation states from successive ionization energies.
13.1.AS2 Explanation of the nature of the coordinate bond within a complex ion.
13.1.AS3 Deduction of the total charge given the formula of the ion and ligands present.
13.1.AS4 Explanation of the magnetic properties in transition metals in terms of unpaired electrons.
13.1.G1 Common oxidation numbers of the transition metal ions are listed in the data booklet in sections 9 and 14.
13.1.IM1 The properties and uses of the transition metals make them important international commodities. Mining for precious metals is a major factor in the economies of some countries.
13.1.ToK1 The medical symbols for female and male originate from the alchemical symbols for copper and iron. What role has the pseudoscience of alchemy played in the development of modern science?
13.1.Aims1 Aim 6: The oxidation states of vanadium and manganese, for example, could be investigated experimentally. Transition metals could be analysed using redox titrations.
13.1.Aims2 Aim 8: Economic impact of the corrosion of iron.
13.2.NoS1 Models and theories—the colour of transition metal complexes can be explained through the use of models and theories based on how electrons are distributed in d-orbitals. (1.10)
13.2.NoS2 Transdisciplinary—colour linked to symmetry can be explored in the sciences, architecture, and the arts. (4.1)
13.2.U1 The d sub-level splits into two sets of orbitals of different energy in a complex ion.
13.2.U2 Complexes of d-block elements are coloured, as light is absorbed when an electron is excited between the d-orbitals.
13.2.U3 The colour absorbed is complementary to the colour observed.
13.2.AS1 Explanation of the effect of the identity of the metal ion, the oxidation number of the metal and the identity of the ligand on the colour of transition metal ion complexes.
13.2.AS2 Explanation of the effect of different ligands on the splitting of the d-orbitals in transition metal complexes and colour observed using the spectrochemical series.
13.2.G1 The spectrochemical series is given in the data booklet in section 15. A list of polydentate ligands is given in the data booklet in section 16.
13.2.G2 Students are not expected to recall the colour of specific complex ions.
13.2.G3 The relation between the colour observed and absorbed is illustrated by the colour wheel in the data booklet in section 17.
13.2.G4 Students are not expected to know the different splitting patterns and their relation to the coordination number. Only the splitting of the 3-d orbitals in an octahedral crystal field is required.
13.2.Aims1 Aim 6: The colours of a range of complex ions, of elements such as Cr, Fe, Co, Ni, and Cu could be investigated
13.2.Aims2 Aim 7: Complex ions could be investigated using a spectrometer data logger.
13.2.Aims3 Aim 8: The concentration of toxic transition metal ions needs to be carefully monitored in environmental systems.
Last Updated: a year ago