The Solubility Curve of KNO3: Lab Procedure

Question: What is the solubility curve predicted by KNO 3: A sketch to show the desired shape of the curve versus the solubility of a typical solid dissolved in water at different temperatures. Solubility is plotted on the y-axis and temperature is plotted on the x-axis. Material: large test tube suitable for test tube equilibrium stirring line double hole stopper, thermometer plugged in a hole 400 mL beaker measuring cylinder or pipette or burette hot plate or Bunsen burner, ring clamp and wire mesh distillation table and thermometer clamp potassium nitrate , KNO 3 distilled water program:

Solubility curves are a common tool used by scientists to understand / provide relationships between solubility, temperature, solvent type. By plotting this information, scientists can find the best solvent / antisolvent, temperature and theoretical yield. As you can see from the figure above, at low supersaturation the crystal grows faster than it nucleates, resulting in a large crystal size distribution. At high supersaturation levels, nucleation dominates crystal growth and provides smaller crystals. This makes it important to understand and control supersaturation in the production of crystals of the required size and distribution.

Crystallization is a technique used by chemists to purify solid compounds. This is one of the basic steps all chemists have to master to master in the laboratory. Crystallization is based on the principle of solubility: Compounds (solutes) are more soluble in hot liquids (solvents) than cold liquids. Upon cooling the saturated hot solution, the solute is no longer soluble in the solvent and forms crystals of the pure compound. Exclude impurities from the grown crystals and separate pure solid crystals from the dissolved impurities by filtration