Note that with heating more solid can generally dissolve (graphs increase). The pH of an aqueous solution can affect the solubility of the solute. Worked example using solubility ratios. Solubility is defined as the upper limit of solute that can be dissolved in a given amount of solvent at equilibrium. 5. A solubility curve shows how the solubility of a salt like sodium chloride or potassium nitrate varies with temperature. - 1 - Solubility Curve of Potassium Nitrate in Water Introduction Background Solutions are homogeneous mixtures of solvents (the larger volume of the mixture) and solutes (the smaller volume of the mixture).For example, a hot chocolate is a solution, in which the solute (the chocolate powder) is dissolved in the solvent (the milk or water). Other iron compounds may be more water soluble than the examples mentioned above. Many iron … By changing the pH of the solution, you can change the charge state of the solute. Solubility is Affected by pH. Looking at the solubility curve above for Barium nitrate, at 60 degrees, 20 g of solid will dissolve in 100g of water (saturated). Iron carbonate has a water solubility of 60 mg/L, iron sulphide of 6 mg/L, and iron vitriol even of 295 g/L. In the acidic range, iron solubility increases as the temperature decreases. Solubility curves. In this experiment, you will construct a solubility curve for KNO 3 The results show that temperature has significant effect on iron solubility in NaCl over the entire pH range. Below 20g at this temperature the solution will be unsaturated. The curves are the calculated values using ... Iron solubility at 5, 25, and 50°C in 0.7 M NaCl solution is shown in Fig. This is the opposite for gases. Two typical solubility curves. the curve, it has less than the maximum amount of solute required for saturation, so the solution is considered unsaturated. The water solubility of some iron compounds increases at lower pH values. The solubility is often (although not always) measured as the mass of salt which would saturate 100 grams of water at a particular temperature. If the solution is above the curve, it is classified as supersaturated because it has more solute than required for saturation in the solution. In such an equilibrium, Le Chatelier's principle can be used to explain most of the main factors that affect solubility.