Complete the table by placing one tick (✓) in each row to indicate the sign of each type of energy change under standard conditions. [Table with energy change types and columns for always positive, always negative, either negative or positive]

1. (a)Complete the table by placing one tick (✓) in each row to indicate the sign of each type of energy change under standard conditions. [Table with energy change types and columns for always positive, always negative, either negative or positive][1]
2. (b)Define, in words, the term enthalpy change of solution.[1]
3. (c)The following enthalpy changes are given. [Table with enthalpy changes and values for formation of K₃PO₄(s), P(s) + 2O₂(g) + 3e⁻ → PO₄³⁻(aq), K(s) → K⁺(aq) + e⁻] Determine the standard enthalpy change of solution of potassium phosphate, K₃PO₄(s). It may be helpful to draw a labelled energy cycle. ΔHsol =[3]
4. (d)Some lattice energy values are shown in the table. [Table with compounds CaBr₂(s) and KBr(s) and their lattice energy values] Suggest an explanation for why ΔHlatt CaBr₂ is more exothermic than ΔHlatt KBr.[2]
5. (e)(i)For a particular gas phase reaction the variation in standard Gibbs free energy change, ΔGᵒ, with temperature is shown. Assume standard enthalpy change, ΔHᵒ, and standard entropy change, ΔSᵒ, remain constant with temperature. [Figure X.X] Write the equation that relates ΔGᵒ to ΔHᵒ and ΔSᵒ.[1]
6. (e)(ii)Use this equation to explain why ΔGᵒ becomes less positive as temperature increases in this reaction.[1]

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