Copper sulphate crystals
Chemijos laboratorinis darbas.
Heat application to turn copper II sulphate and changes of state. Hydrated copper II sulphate solid ⇄ anhydrous copper sulphate solid. + water gas. Materials used. Mass 1 =. Mass 2 =. Mass 3 =. G moles.
The aim is to show that this chemical reaction is reversible: it will go both directions under the high temperature. As the copper II sulphate has crystallisation water in their structure, we call it hydrated copper (II) sulphate.
Evaporating dish with the hydrated copper sulphate was placed on the heat resistant mat with the tripod. Bunsen burner was set on the strong blue flame, in order to heat the product. During the process, sizzling was heard, the product started to change colour from blue to white. Throughout the heating vapour was seen, as well as gas smelled. The hydrated copper sulphate was heated till it changed colour completely from blue to white and there was no more vapour seen. After evaporating dish was left to cool down, and weighted again, Mass 3 = 51.46g.
20ml of distilled water was added to the beaker and anhydrous copper sulphate was added to it. It was observed that colour changed from white to blue straight away. Some product dissolved and some heat was felt by touching the glass beaker. The beaker with the product was placed back on the Bunsen burner and gently stirred until it boiled and the rest of the copper sulphate dissolved. The colour went back to blue.