Solution :
a). Applying the energy balance,



![$0=[mc(T_f-T_i)_{iron}] + [mc(T_f-T_i)_{water}]$](https://tex.z-dn.net/?f=%240%3D%5Bmc%28T_f-T_i%29_%7Biron%7D%5D%20%2B%20%5Bmc%28T_f-T_i%29_%7Bwater%7D%5D%24)


b). The entropy change of iron.


= -9.09 kJ-K
Entropy change of water :


= 10.76 kJ-K
So, the total entropy change during the process is :

= -9.09 + 10.76
= 1.67 kJ-K
c). Exergy of the combined system at initial state,






Therefore, energy of the combined system at the initial state is

= 63.94 -13.22
= 50.72 kJ
Similarly, Exergy of the combined system at initial state,





Thus, energy or the combined system at the final state is :

= 216.39 - 9677.95
= -9461.56 kJ
d). The wasted work



= 50.72 + 9461.56
= 9512.22 kJ
The answer here would be 14.9 %KCl and here is how I can explain why:
33.5g / 225.6g x 100% = 14.9%
<span>you are looking for % of KCl in the solution, you have to add the mass of the KCl and water to get the total mass of the solution
Hope this helps a lot
</span>
Answer: it is A.
Explanation:
Compare the electric force and gravitational force. ... Both forces are inversely proportional to the square of the distance between the objects, this is known as the inverse-square law. ... If there are two charges that are DIFFERENT, they attract.