In: Chemistry
A mixture is made by combining 19.9 mL of 1.2×10−3 M KSCN, 8.5 mL of 8.1×10−2 M Fe(NO3)3, and 11 mL of 0.198 M HNO3. Calculate the concentration of Fe3+ in the solution.
Answer. given concentration of ferric nitrate is 8.1x10-2 M and volume is 8.5 ml.
first finding the mass of ferric ions in the given concentration
.mass of Fe+3 ions m=(molarity*volume*molar mass)/1000
m=(8.1x10-2*8.5*55.85) /1000
m=3.85x10-2 g/mol.
Now finding the concentration of ferric ions in the mixture.total volume of the mixture=8.5+11+19.9=39.4 ml.
molarity =(3.85x10-2 x1000)/(55.85x39.4)=38.5/2200.49=0.02M
concentration of Fe+3=0.02 M