forces, that all particles are represented as spheres and that the spheres are solid. 4.2.2.2 In chemical equations, the Include appropriate state 0.5 Describe balanced three states of matter are symbols in chemical symbol equations shown as (s), (l) and (g), equations for the including the states of with (aq) for aqueous reactions in this matter. solutions. specification. 4.2.2.3 Ionic compounds have Knowledge of the 1 Extended writing: Research some uses of Video clip regular structures (giant structures of specific describe the electrical ionic substances. YouTube: ionic lattices) in which ionic compounds other conductivity of ionic Extension: make links there are strong than sodium chloride is substances. between the uses of electrostatic forces of not required. ionic substances, their attraction in all directions Extended writing: explain properties and structure. between oppositely why solid ionic charged ions. substances do not Practically test the These compounds have conduct electricity but conductivity of ionic high melting points and dissolved or molten ionic compounds, eg sodium high boiling points substances do conduct chloride and potassium because of the large electricity. chloride. amounts of energy needed to break the many strong Grade 9: explain how bonds. ionic substances dissolve When melted or dissolved in water. in water, ionic compounds conduct electricity Extended writing: explain because the ions are free why sodium chloride is to move and so charge difficult to melt. can flow. 4.2.2.4 Substances that consist of Students should be able 0.5 Extended writing: Research some uses of Video clip molecules are usually to use the idea that describe melting points covalent substances. YouTube: gases or liquids that have intermolecular forces are and boiling points of relatively low melting weak compared with covalent substances. Extension: make links points and boiling points. covalent to explain between the uses of
forces, that all particles are represented as spheres and that the spheres are solid. 4.2.2.2 In chemical equations, the three states of matter are shown as (s), (l) and (g), with (aq) for aqueous solutions. Include appropriate state symbols in chemical equations for the reactions in this specification. 0.5 Describe balanced symbol equations including the states of matter. 4.2.2.3 Ionic compounds have regular structures (giant ionic lattices) in which there are strong electrostatic forces of attraction in all directions between oppositely charged ions. These compounds have high melting points and high boiling points because of the large amounts of energy needed to break the many strong bonds. When melted or dissolved in water, ionic compounds conduct electricity because the ions are free to move and so charge can flow. Knowledge of the structures of specific ionic compounds other than sodium chloride is not required. 1 Extended writing: describe the electrical conductivity of ionic substances. Extended writing: explain why solid ionic substances do not conduct electricity but dissolved or molten ionic substances do conduct electricity. Grade 9: explain how ionic substances dissolve in water. Extended writing: explain why sodium chloride is difficult to melt. Research some uses of ionic substances. Extension: make links between the uses of ionic substances, their properties and structure. Practically test the conductivity of ionic compounds, eg sodium chloride and potassium chloride. Video clip YouTube: 4.2.2.4 Substances that consist of molecules are usually gases or liquids that have relatively low melting points and boiling points. Students should be able to use the idea that intermolecular forces are weak compared with covalent to explain 0.5 Extended writing: describe melting points and boiling points of covalent substances. Research some uses of covalent substances. Extension: make links between the uses of Video clip YouTube:
AQA-8462-SOW-BOND.DOCX