Question

Accurately calculate the concentration of the diluted solution starting with the concentration of the stock fe(no3)3 solution (0.2 m).

Answer 1

Ans: 25 mM

For example, suppose we take the following concentrations:

Diluted Fe$(NO_{3})_{3}$ =1 ml 

1 M KSCN = 5 ml 

0.1 M HN$O_{3}$ = 2  ml 
----------------------------------------
Then, total volume = 8 ml 

Now, 
 final concentration of  diluted Fe$(NO_{3})_{3}$ =$\frac{Concentration - of Fe(NO_{3})_{3}*Volume of Fe(NO_{3})_{3}}{Total Volume}$ 

given stock solution is 0.2 M

Thus, concentration of diluted solution = $\frac{0.2*1}{8} = 0.025 M = 25 milli M$