The answer is C because you must do all the other things first to get to the that’s part hope that helps
Answer : The reaction is endothermic.
Explanation :
Formula used :

where,
= change in temperature = 
Q = heat involved in the dissolution of KCl = ?
m = mass = 0.500 + 50.0 = 50.5 g
c = specific heat of resulting solution = 
Now put all the given value in the above formula, we get:


The heat involved in the dissolution of KCl is positive that means as the change in temperature decreases then the reaction is endothermic and as the change in temperature increases then the reaction is exothermic.
Hence, the reaction is endothermic.
Answer:
2.33g of iron (iii) chloride
50.0 mL of 5.00 M of sodium phosphate
FeCl3 + Na3PO4 > Fe(PO4) + 3NaCl
mol = conc × vol = 0.5 × 50/1000 = 0.025 mol Na3PO4
from the equation:
1 mol of Na3PO4 reacts with 1 mol FeCl3 = 3 mol of NaCl
0.025 mol = x
x = 0.0025 × 3 = 0.075 mol NaCl
mass = 0.075 g × 59 g/mol = 4.425 g NaCl
i guessed all of this so i dont know i it is correct