In the experiment you have added 50.0 mL of Ni(H2O)6

2+ to the calorimeter. To this you
add 5.0 mL of ethlylenediamine and measure the change in temperature of the solution as
the reaction proceeds. The temperature increases by 3.4 oC. Calculate the enthalpy (H)
for this reaction in kJ/mol. [ Answer: -1.0x102 kJ/mol ]

You don't give any concentrations. I don't see any way to solve for mols.

To calculate the enthalpy change (ΔH) for this reaction in kJ/mol, we can use the equation:

ΔH = q / (moles of limiting reactant)

First, let's determine the moles of the limiting reactant, which in this case is Ni(H2O)6 2+.

To calculate the moles of Ni(H2O)6 2+, we need to know its molarity and volume.

However, the given information doesn't provide the molarity of Ni(H2O)6 2+ or its concentration. Without this information, it is not possible to calculate the moles of the limiting reactant.

Therefore, without the molarity of the reactant, we cannot accurately determine the enthalpy change (ΔH) for this reaction.