State the relative charges and approximate relative masses of protons, neutrons and electrons Define proton number (atomic number) as the number of protons in the nucleus of an atom Define nucleon number (mass number) as the total number of protons and neutrons in the nucleus of an atom Use proton number and the simple structure of atoms to explain the basis of the Periodic Table, with special reference to the elements of proton number Define isotopes as atoms of the same element which have the same proton number but a different nucleon number Understand that isotopes have the same properties because they have the same number of electrons in their outer shell State the two types of isotopes as being radioactive and non-radioactive State one medical and one industrial use of radioactive isotopes Describe the build-up of electrons in ‘shells’ and understand the significance of the noble gas. electronic structures and of the outer shell electrons. Explain Inertness of group zero elements.

Describe the Periodic Table as a method of classifying elements and its use to predict properties of elements. Describe the change from metallic to nonmetallic character across a period. Describe and explain the relationship between Group number, number of outer shell electrons and metallic/non-metallic character. Describe lithium, sodium and potassium in Group I as a collection of relatively soft metals showing a trend in melting point, density and reaction with water. Predict the properties of other elements in Group I, given data, where appropriate

Describe the differences between elements, mixtures and compounds, and between metals and non-metals Describe an alloy, such as brass, as a mixture of a metal with other elements Describe the formation of ionic bonds between metallic and non-metallic elements. Describe the lattice structure of ionic compounds as a regular arrangement of alternative positive and negative ions. Describe the formation of single covalent bonds in H2, Cl2, H2O, CH4, NH3 and HCl as the sharing of pairs of electrons leading to the noble gas configuration. Describe the electron arrangement in more complex covalent molecules such as N2, C2H4, CH3OH and CO2. Describe the macromolecular structure of silicon(IV) oxide (Silicon dioxide) Describe the similarity in properties between diamond and silicon (IV) oxide, related to their structures. Describe the differences in volatility, solubility, electrical conductivity between ionic and covalent compounds. Explain the differences in melting point and boiling point of ionic and covalent compounds in terms of attractive forces.

Name appropriate apparatus for the measurement of time, temperature, mass and volume, including burettes, pipettes and measuring cylinders Demonstrate knowledge and understanding of paper chromatography Interpret simple chromatograms, including the use of Rf values Outline how chromatography techniques can be applied to colourless substances by exposing chromatograms to substances called locating agents.