To analyse how copper is obtained from oxidised copper ore using the processes of leaching, solid-liquid separation, displacing and electrowinning.
Refer to ‘Extraction of Copper from oxidised Copper Ore’ document pages 1-2
The blue particles in the copper ore which is copper was dissolved in the sulphuric acid and the solution turned into a blue colour. There was also sediment that was floating around in the solution. Solid-liquid separation:
Sedimentation took place and after leaving the beaker for a while, the sediment went from floating around in the beaker to slowly moving towards the bottom of the beaker and settling there. The liquid in the solution remained the blue colour from before. Cementation:
The steel wool turned into a brown colour where it had been in contact with the sulphuric acid with copper dissolved into it. The copper attached onto the steel wool and it was replaced by the steel wool. The liquid was not blue anymore and it was a clear colour. Electrowinning:
Bubbles formed around the electrodes as soon as they entered the solution. Bubbles formed around both of the electrodes but more on the black electrode. The light bulb turned on which meant that electricity was being conducted. The copper plated on the black coloured electrode and the liquid tuned into a greenish colour.
1.During the cementation process (displacement reaction):
a)Why did the solution lose its blue colour over time?
The solution lost its blue colour over time because the solution was originally a clear colour because of the sulphuric acid but during the leaching process, the copper was dissolved into the sulphuric acid giving it its blue colour. During the cementation process, the copper was replaces with the iron as it was more reactive, therefore the copper swapped places with the iron, as shown by the brown colour and then the solution became clear...