Topic 2: Atomic Structure and the Periodic Table

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

Use —the structure of an atom in terms of electrons, protons and neutrons to connect the rule to the data and decision in the question.

This matters because —the structure of an atom in terms of electrons, protons and neutrons determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the structure of an atom in terms of electrons, protons and neutrons to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The structure of an atom in terms of electrons, protons and neutrons is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —the relative mass and charge of protons, neutrons and electrons to connect the rule to the data and decision in the question.

This matters because —the relative mass and charge of protons, neutrons and electrons determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the relative mass and charge of protons, neutrons and electrons to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The relative mass and charge of protons, neutrons and electrons is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —what is meant by the terms ‘atomic (proton) number’ and ‘mass number’ to connect the rule to the data and decision in the question.

This matters because —what is meant by the terms ‘atomic (proton) number’ and ‘mass number’ determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —what is meant by the terms ‘atomic (proton) number’ and ‘mass number’ to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —What is meant by the terms ‘atomic (proton) number’ and ‘mass number’ is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —the atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion to connect the rule to the data and decision in the question.

This matters because —the atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand the term ‘isotope’.

Use —the term ‘isotope’ to connect the rule to the data and decision in the question.

This matters because —the term ‘isotope’ determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the term ‘isotope’ to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The term ‘isotope’ is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —the basic principles of a mass spectrometer to connect the rule to the data and decision in the question.

This matters because —the basic principles of a mass spectrometer determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the basic principles of a mass spectrometer to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The basic principles of a mass spectrometer is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —predict mass spectra to connect the rule to the data and decision in the question.

This matters because —predict mass spectra determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —predict mass spectra to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Predict mass spectra is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —define first, second and third ionisation energies and understand that all ionisation energies are endothermic to connect the rule to the data and decision in the question.

This matters because —define first, second and third ionisation energies and understand that all ionisation energies are endothermic determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —define first, second and third ionisation energies and understand that all ionisation energies are endothermic to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Define first, second and third ionisation energies and understand that all ionisation energies are endothermic is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —an orbital is a region within an atom that can hold up to two electrons with opposite spins to connect the rule to the data and decision in the question.

This matters because —an orbital is a region within an atom that can hold up to two electrons with opposite spins determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —an orbital is a region within an atom that can hold up to two electrons with opposite spins to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —An orbital is a region within an atom that can hold up to two electrons with opposite spins is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —how ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell to connect the rule to the data and decision in the question.

This matters because —how ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —how ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —How ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —ideas about electronic structure developed from: i an understanding that successive ionisation energies provide evidence to connect the rule to the data and decision in the question.

This matters because —ideas about electronic structure developed from: i an understanding that successive ionisation energies provide evidence determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —ideas about electronic structure developed from: i an understanding that successive ionisation energies provide evidence to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Ideas about electronic structure developed from: i an understanding that successive ionisation energies provide evidence is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Be able to describe the shapes of s and p orbitals.

Use —the shapes of s and p orbitals to connect the rule to the data and decision in the question.

This matters because —the shapes of s and p orbitals determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the shapes of s and p orbitals to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The shapes of s and p orbitals is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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

Use —orbitals in sub-shells: i each take a single electron before pairing up ii pair up with two electrons of opposite spin to connect the rule to the data and decision in the question.

This matters because —orbitals in sub-shells: i each take a single electron before pairing up ii pair up with two electrons of opposite spin determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —orbitals in sub-shells: i each take a single electron before pairing up ii pair up with two electrons of opposite spin to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Orbitals in sub-shells: i each take a single electron before pairing up ii pair up with two electrons of opposite spin is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions to connect the rule to the data and decision in the question.

This matters because —predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand that electronic configuration determines the chemical properties of an element.

Use —electronic configuration determines the chemical properties of an element to connect the rule to the data and decision in the question.

This matters because —electronic configuration determines the chemical properties of an element determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —electronic configuration determines the chemical properties of an element to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Electronic configuration determines the chemical properties of an element is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —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 to connect the rule to the data and decision in the question.

This matters because —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 determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —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 to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —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 is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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’.

Use —represent data, in a graphical form (including the use of logarithms of first ionisation energies on a graph) for elements 1 to connect the rule to the data and decision in the question.

This matters because —represent data, in a graphical form (including the use of logarithms of first ionisation energies on a graph) for elements 1 determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —represent data, in a graphical form (including the use of logarithms of first ionisation energies on a graph) for elements 1 to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Represent data, in a graphical form (including the use of logarithms of first ionisation energies on a graph) for elements 1 is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

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.

Use —explain: i the trends in melting and boiling temperatures of the elements of periods 2 and 3 of the periodic table in terms to connect the rule to the data and decision in the question.

This matters because —explain: i the trends in melting and boiling temperatures of the elements of periods 2 and 3 of the periodic table in terms determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —explain: i the trends in melting and boiling temperatures of the elements of periods 2 and 3 of the periodic table in terms to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Explain: i the trends in melting and boiling temperatures of the elements of Periods 2 and 3 of the Periodic Table in terms is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.