Copper can be recovered from copper (II) sulphate solution by a displacement reaction with aluminium(a) Write balanced equation(b) what is minimum mass of aluminium that would be required to recover 1 kg of copper?
a) 2Al (solid) + 3CuSO4 (aqueous)--> Al2(SO4)3 (aqueous)+ 3Cu (aqueous) Charge of SO4 [sulfate] is -2 [This can be concluded because it is copper II solution which means the copper has a charge of +2] Charge of Al is +3 so two aluminiums and 3 SO4 makes a charge of 0. Since Al has become a 2, the other side needs to have a 2 infront. SO4 amount has changed to 3 so other side needs a 3 infront of copper sulfate. The copper has been changed to 3 so the right hand side should be 3Cu. 2. By Molar ratio [proportions of mol] Al:Cu is 2:3 Mol = mass / molar mass For copper... mol = 1000g/63.54 {check up periodic table for molar mass} mol = 15.74 From the above, By Molar ratio Al:Cu is 2:3 therefore, every 3 mol of Cu, 2 mol of Al is needed. Therefore 10.5mol of Al is needed to cover 15.74mol of Cu. To convert to grams. Use mass= mol x molar mass Al's molar mass is 26.98 mass= 10.5 x 26.98 =283.29g Hope this helps!
Impractical ... oxide layer on the aluminium makes the reaction extremely slow and, indeed, it may well not occur at all. However ... 2Al + 3CuSO4 --> Al2(SO4)3 + 3Cu. Ar(Cu)=63.5; Ar(Al)=27 So 2*27=54g of Al will produce 3*63.5=190.5g of Cu So to give 1000g of Cu [(54/190.5)*1000]g of Al are required. =283.5g
2Al(s) + 3CuSo4 --> Al2(So4)3 + 2Cu(s) or ionically 2Al(s) +3 Cu2+ ---> 2 Al3+(aq) +2Cu(s) ok, i confess. it's been years since i finished my A-Levels so i forgot about this single displacement reaction. lol.
