Consider the following reversible chemical reaction. Imagine that you have prepared a solution of FeSCN2+ which is initially blood red in color. Answer the following questions about the equilibrium shifts and color changes that result from various chemical changes.
Fe3+ (aq) + SCN-(aq) FeSCN2+(ag)
1
..t
yellow
colorless blood red
1. First, several drops of concentrated iron nitrate (Fe(NO3)3) are added to the red solution. As a result, the solution will
turn darker red
2. You know that the iron(II) ions (Fe3+) will combine with chloride ions (Cl) to form an insoluble salt (FeCl3) that precipitates out of solution. If you
add a scoop of sodium chloride (NaCl) to the solution, it will turn lighter red/orange
3. Now a milliliter of concentrated potassium nitrate (KSCN) solution is added to the solution, making it not change color
4. You know that silver ions (Ag) will combine with thiocyanate ions (SCN) to form an insoluble salt (AgSCN) that precipitates out of solution. If you
add silver ions to this solution, it will turn darker red
V
5. You also know that this is an endothermic reaction. If you heat this solution to raise the temperature, it will
QUESTION 5