Define standard electrode potential, E°, including a description of standard conditions.

1. (a)Define standard electrode potential, E°, including a description of standard conditions.[2]
2. (b)(i)An electrochemical cell is set up to measure E° of the Ag⁺(aq)/Ag(s) electrode. Draw a labelled diagram of this electrochemical cell. Include all necessary substances. It is not necessary to state conditions used.[3]
3. (b)(ii)A separate electrochemical cell is set up using a lower concentration of Ag⁺(aq) than that used in (b)(i). Suggest how the electrode potential, E, for the Ag⁺(aq)/Ag(s) electrode would change from its E° value. Explain your answer.[1]
4. (c)Define enthalpy change of solution, ΔH°sol.[1]
5. (d)(i)Some relevant energy changes for AgNO₃ are shown in Table 4.1. Table 4.1 energy change value/kJmol⁻¹ enthalpy change of solution of AgNO₃(s) +22.6 enthalpy change of hydration of silver ions -475 enthalpy change of hydration of nitrate ions -314 Complete the energy cycle in Fig. 4.1 to show the relationship between the lattice energy, ΔH°latt, of AgNO₃(s) and the energy changes shown in Table 4.1. Include state symbols for all the species. [Figure 4.1][2]
6. (d)(ii)Calculate the lattice energy, ΔH°latt, of AgNO₃(s).[1]
7. (e)Suggest the trend in the magnitude of the lattice energies of the metal nitrates, NaNO₃(s), Mg(NO₃)₂(s) and RbNO₃(s). Explain your answer. most exothermic least exothermic[3]

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