Metallic bonding and types of crystal structureAQA A-Level Chemistry: Mind map

Exam questions on Metallic bonding and types of crystal structure

1. A technician is testing four unlabelled solids at room temperature. Solid W conducts electricity, is malleable and melts at 650 °C. Solid X does not conduct as a solid, conducts when molten and melts at 801 °C. Solid Y does not conduct in any state and melts at 114 °C. Solid Z is very hard, does not conduct and melts above 3500 °C.
   Explain why solid X conducts electricity when molten but not when solid.2 marks
2. A student compares sodium, which melts at 98 °C, with magnesium, which melts at 650 °C. Both metals conduct electricity as solids and both can be hammered into shape.
   Explain why sodium can be hammered into shape without breaking.2 marks
3. Graphite and diamond are both forms of carbon. Graphite is used as electrodes and as the 'lead' in pencils, which leave a mark because layers rub off onto paper. Diamond is used on the cutting edges of drill bits.
   Explain why graphite conducts electricity but diamond does not.3 marks