The large collection at the back of my wardrobe is a testament to the fact that I have always displayed a keen interest in crystals and the similarities and differences in their structure and properties. In this experiment, I will chart the solubility of two sulfate salts (CuSO4 and ZnSO4) in a solution with the liquid solvent water (H2O). Solubility is defined as the maximum weight of anhydrous solute that will dissolve in 100 g of solvent. I used water as the solvent because this is what is used in the food industry, and the nature of the real life problem interested me . I aim to see to what extent reaching an equilibrium (i.e. saturation, when the properties of the solution will remain constant) is dependent on temperature, and what …show more content…
In trying to come up with a detailed plan I found the experiment outline published on the website (http://www.chymist.com/Solubility%20salt.pdf ) and used this to aid me in my planning, although I adapted it for the particulars I wanted to include in my own experiment. So after making the solid crystals, I set up the apparatus with clamp, stand and boss holding a boiling tube over the Bunsen burner, with another clamp holding the thermometer so that the bulb was suspended in the boiling tube, being careful for it not to touch any of its sides. 3. I then took my single copper sulfate crystal and recorded the mass (see quantities table on following page). 4. I collected zinc sulfate crystals to a similar mass, and added both to separate clean dry test tubes. I knew I would need slightly more copper sulfate, as the relative atomic mass of copper is lower than of zinc (although they are very similar in this respect, making it easy to compare results). 5. I measured small amounts of distilled water in a 10cm3 measuring cylinder, weighed the cylinder, and added the water to my salt which I had placed in preparation in a different boiling tube. I then obtained the mass of H2O used by subtracting the weight of the empty measuring cylinder from the original weight of the measuring cylinder which still contained the water; the difference between the two masses was that of the water