WJEC Chemistry for AS Level: Revision Workbook

UNIT 1 PRACTICE PAPER SECTION A 1. Sodium forms Na + ions in most of its compounds. (a) Write the electronic structure of a sodium ion. [1] ......................................................................................................................................................................................................................................................................................................................................... (b) Write the equation that represents the first ionisation energy of sodium. [1] ......................................................................................................................................................................................................................................................................................................................................... 2. Define pH. [1] ......................................................................................................................................................................................................................................................................................................................................... 3. Magnesium and aluminium are both electrical conductors. Explain why aluminium is a better conductor than magnesium. [2] ......................................................................................................................................................................................................................................................................................................................................... ......................................................................................................................................................................................................................................................................................................................................... ......................................................................................................................................................................................................................................................................................................................................... ......................................................................................................................................................................................................................................................................................................................................... 4. Use a dot-and-cross diagram to show the bonding in calcium fluoride. [2] 5. The first line of the Balmer series of the emission spectrum of hydrogen has a frequency of 4.57 × 10 14 Hz. (a) State which energy levels are involved in the transition that produces this line. [1] ......................................................................................................................................................................................................................................................................................................................................... (b) Calculate the energy of the transition that produces this line, in kJ mol −1 . [2] Energy = ............................................................................................. kJ mol −1 Unit 1 Practice paper | 153 Unit 1 Practice paper