what would be the initial concentration (M) for Fe+3 if you have
2.00 x 10-3 M Fe(NO3)3 in 1 M HNO3 ((ml) 5.00)
2.00 x 10-3 M KSCN ((ml) 1.00)
Distilled water ((ml) 4.00)
Before any reaction takes place you have
5 mL of 2E-3 M Fe(NO3)2 in 10 mL total volume (5 + 1 + 4 = 10).
So 2E-3 M x (5 mL/10 mL) = ? M for (Fe^3+)
To find the initial concentration of Fe+3 in this solution, you will need to consider the dilution caused by adding distilled water and the reaction that occurs between Fe+3 and SCN-.
First, let's calculate the total volume of the solution.
Total volume = volume of Fe(NO3)3 solution + volume of KSCN solution + volume of distilled water
Total volume = 5.00 mL + 1.00 mL + 4.00 mL = 10.00 mL
Next, let's calculate the moles of Fe+3 initially present in the Fe(NO3)3 solution.
Moles of Fe+3 = initial concentration of Fe+3 × volume of Fe(NO3)3 solution
Moles of Fe+3 = (2.00 x 10^-3 M) × (5.00 mL ÷ 1000 mL/1 L) = 1.00 x 10^-5 moles
Now, let's calculate the final volume of the solution after dilution with distilled water.
Final volume = volume of Fe(NO3)3 solution + volume of KSCN solution = 5.00 mL + 1.00 mL = 6.00 mL
Since the reaction between Fe+3 and SCN- will form a 1:1 complex, the moles of Fe+3 will be equal to the moles of SCN- in the final solution.
The final concentration of Fe+3 can be calculated using the following equation:
Final concentration of Fe+3 = moles of Fe+3 / final volume
Final concentration of Fe+3 = (1.00 x 10^-5 moles) / (6.00 mL ÷ 1000 mL/1 L)
Final concentration of Fe+3 = 1.67 x 10^-3 M
Therefore, the initial concentration of Fe+3 in the provided solution is 1.67 x 10^-3 M.