Complete the table for coordination number and number of particles per unit cell.

Welcome back Gobte — missed you this week. c) Step 1: Complete the table for coordination number and number of particles per unit cell. | Type of unit cell | Coordination number | Number of particles per unit cell | | :---------------------------- | :------------------ | :-------------------------------- | | Cubic close pack or face centered cubic | 12 | 4 | | Body centered cubic | 8 | 2 | d) i) Lattice energy is the energy change when one mole of an ionic compound is formed from its gaseous ions under standard conditions. It is a measure of the strength of the electrostatic forces between ions in a crystal lattice. ii) Born-Haber cycle for the formation of sodium oxide (Na_2O). The overall reaction is: 2Na(s) + (1)/(2)O_2(g) → Na_2O(s) c 2Na(s) + (1)/(2)O_2(g) H_f Na_2O(s) \\ 2 H_atom(Na) \\ 2Na(g) + (1)/(2)O_2(g) \\ H_atom(O) \\ 2Na(g) + O(g) \\ 2IE_1(Na) \\ 2Na^+(g) + O(g) + 2e^- \\ EA_1(O) \\ 2Na^+(g) + O^-(g) + e^- \\ EA_2(O) \\ 2Na^+(g) + O^2-(g) \\ U_L \\ Na_2O(s) iii) From the Born-Haber cycle, the expression for the lattice energy (U_L) of sodium oxide is: U_L = H_