Ch 11: Solution Formation Solution- a homogeneous mixture - Can be g & g, l & l, s & s, g & l l & s g & s Miscible- Immiscible- http://www.bozemanscience.com/ap-chem-015-solutions (9:46)

11.2 Heat of Solution The Heat of Solution is the amount of heat energy absorbed (endothermic) or released (exothermic) when a specific amount of solute dissolves in a solvent. Substance Heat of Solution (kJ/mol) NaOH -44.51 NH4NO3 +25.69 KNO3 +34.89 HCl -74.84

Steps in Solution Formation H1 Step 1 - Expanding the solute Separating the solute into individual components

Steps in Solution Formation H2 Step 2 - Expanding the solvent Overcoming intermolecular forces of the solvent molecules

Steps in Solution Formation H3 Step 3 - Interaction of solute and solvent to form the solution

Predicting Solution Formation Solvent/ Solute H1 H2 H3 Hsol’n Outcome Polar/ Polar + large - large +/-small Solution forms Nonpolar + small +/- small No solution Nonpolar/ +/- small polar

Example Use this data to calculate the enthalpy of hydration for calcium chloride and calcium iodide. Lattice Energy Delta Hsoln CaCl2(s) -2247 kJ/mol -46 kJ/mol CaI2(s) -2059 kJ/mol -104 kJ/mol Ch 11 p. 520, #34 Based on your answer, which ion, Cl- or I-, is more strongly attracted to water?

Solubility Chart