‘Fixed Mass’ Method

• 1. Accurately measure a known mass of a solute into a boiling tube (E.G. ammonium chloride) and add to measured volume of water.
• 2. Heat the mixture using a hot water bath until all of the solute (solid) dissolves in the water.
• 4. Place thermometer into solution and remove from hot water bath to allow to cool (can use cold water bath to speed up process).
• 5. Record the temperature at which crystals first start to appear.
• 6. Repeat this several times with increasing volumes of water (like 1cm^3).
• 7. Able to determine solubility at each temperature:

  • Solubility = mass of solute / volume of water x 100