flavouring, leaving behind the polymer). Mass can be measured before and after. 5.2.2.6 Substances that consist of Recognise giant covalent 1 Use the results of experiments Compare the properties of giant covalent structures are structures from diagrams to determine whether the sugar table salt, sugar and paraffin solids with very high melting showing their bonding and (covalent), table salt (ionic) and wax. points. structure. paraffin wax (covalent) are covalent or ionic compounds. Test the melting point of the All of the atoms in these WS 1.2 three substances by heating structures are linked to other on an aluminium foil boat. atoms by strong covalent MS 5b Test the solubility by bonds. These bonds must be dissolving each material in overcome to melt or boil distilled water. these substances. Test the conductivity of the Diamond and graphite (forms compounds from the of carbon) and silicon dioxide solubility test. (silica) are examples of giant covalent structures. 5.2.2.7 Metals have giant structures Explain why alloys are harder 1 Describe the structure of metals. Model alloys using plasticine Video clips: of atoms with strong metallic than pure metals in terms of and various amounts of sand bonding. This means that distortion of the layers of Describe melting points and and test how ductile it is (pull most metals have high atoms in the structure of a boiling points of metals and why a cylinder of sand-plasticine melting and boiling points. pure metal. they are high. mix apart). In pure metals, atoms are WS 1.2 Describe the structure of metal arranged in layers, which alloys. allows metals to be bent and shaped. Pure metals are too soft for many uses and so are mixed with other metals to make alloys which are harder..
flavouring, leaving behind the polymer). Mass can be measured before and after. 5.2.2.6 Substances that consist of giant covalent structures are solids with very high melting points. All of the atoms in these structures are linked to other atoms by strong covalent bonds. These bonds must be overcome to melt or boil these substances. Diamond and graphite (forms of carbon) and silicon dioxide (silica) are examples of giant covalent structures. Recognise giant covalent structures from diagrams showing their bonding and structure. WS 1.2 MS 5b 1 Use the results of experiments to determine whether the sugar (covalent), table salt (ionic) and paraffin wax (covalent) are covalent or ionic compounds. Compare the properties of table salt, sugar and paraffin wax. Test the melting point of the three substances by heating on an aluminium foil boat. Test the solubility by dissolving each material in distilled water. Test the conductivity of the compounds from the solubility test. 5.2.2.7 Metals have giant structures of atoms with strong metallic bonding. This means that most metals have high melting and boiling points. In pure metals, atoms are arranged in layers, which allows metals to be bent and shaped. Pure metals are too soft for many uses and so are mixed with other metals to make alloys which are harder.. Explain why alloys are harder than pure metals in terms of distortion of the layers of atoms in the structure of a pure metal. WS 1.2 1 Describe the structure of metals. Describe melting points and boiling points of metals and why they are high. Describe the structure of metal alloys. Model alloys using plasticine and various amounts of sand and test how ductile it is (pull a cylinder of sand-plasticine mix apart). Video clips:
AQA-8464F-SOW-BOND.DOCX