EXPERIMENTAL: AN INVESTIGATION INTO THE RELATIONSHIP BETWEEN THE ENERGY
RELEASED AND THE CONCENTRATION OF REACTANTS IN A DISPLACEMENT REACTION
Introduction A displacement reaction is the chemical change which occurs when a more reactive element displaces a less reactive element from its compound;
e.g., 2Al(s) + 3CuSO4(aq) 覧覧覧覧覧 Al2(SO4)3(aq) + 3Cu(s)
In this redox reaction, electrons are transferred from aluminium atoms to copper(II) ions because aluminium is a better reducing agent (i.e., it is more easily oxidized); the redox half equations are:
2Al(s) 覧覧覧覧覧 2Al3+(aq) + 6e-
3Cu2+(aq) + 6e- 覧覧覧覧覧 3Cu(s)
The aqueous sulfate ions are spectators, so the net ionic equation is:
2Al(s) + 3Cu2+(aq) 覧覧覧覧覧 2Al3+(aq) + 3Cu(s)
[.. K > Ca > Na > Mg > Al > Zn > Fe > Sn > Pb > (H) > Cu > Hg > Ag ..]
For the reaction of aluminium with aqueous copper(II) sulfate, in the
presence of sodium chloride, you are required to investigate whether 
there is a direct relationship between the heat energy released and
the concentration of aqueous copper(II) sulfate; i.e., H = k ラ C ?
Notes
1.  Aqueous chloride ions facilitate the removal of the very thin oxide
layer which invariably covers aluminium: however, they do not catalyze
the reaction between (pure) aluminium and aqueous copper(II) sulfate.
2. The heat energy released from a chemical reaction can be determined by first measuring its temperature change, and then using the equation H = mcDT, where: H is the heat energy released; m is the mass of substance; c is its specific heat capacity; and DT is the temperature change. [Assume that 1.00 cmウ of aqueous copper(II) sulfate has a mass of 0.001 kg, and that its specific heat capacity is 4200 J kg-ケ K-ケ.]
3. You are provided with aluminium powder, aqueous copper(II) sulfate (with an initial concentration of 0.300 mol dm-ウ), distilled water, and sodium chloride. In addition, you will need to use - within reason - suitable apparatus.
4. The proposed plan of your investigation should be presented in detail; this plan may be modified as the investigation proceeds.
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