100ml of 0.1n feso4 solution will be compelety oxidised by x gms of k2...
Introduction
To determine the amount of K2Cr2O7 required to completely oxidize 100 ml of 0.1 N FeSO4 solution in an acidic medium, we follow these steps:
Step 1: Calculate the moles of FeSO4
- Normality (N) of FeSO4 = 0.1 N
- Volume (V) = 100 ml = 0.1 L
- Moles of FeSO4 = Normality × Volume = 0.1 × 0.1 = 0.01 equivalents
Step 2: Determine the equivalents of Fe2+
- Each mole of FeSO4 provides one equivalent of Fe2+.
- Thus, equivalents of Fe2+ = 0.01 eq.
Step 3: Stoichiometry of the reaction
- The balanced redox reaction in acidic medium is:
6 Fe2+ + Cr2O7^2- + 14 H+ → 6 Fe3+ + 2 Cr3+ + 7 H2O
- From the equation, 1 equivalent of Cr2O7^2- oxidizes 6 equivalents of Fe2+.
Step 4: Calculate equivalents of K2Cr2O7 needed
- Since 6 equivalents of Fe2+ require 1 equivalent of Cr2O7^2-, we can set up the proportion:
- For 0.01 eq of Fe2+, the equivalents of Cr2O7^2- needed = 0.01 / 6 = 0.00167 eq.
Step 5: Calculate grams of K2Cr2O7
- Molar mass of K2Cr2O7 = 294 g/mol
- Since 1 mol of K2Cr2O7 = 6 equivalents, the equivalent weight = 294 / 6 = 49 g/eq.
- Thus, mass of K2Cr2O7 needed = 0.00167 eq × 49 g/eq = 0.08183 g.
Conclusion
The value of x, the mass of K2Cr2O7 required, is approximately 0.0818 g.
100ml of 0.1n feso4 solution will be compelety oxidised by x gms of k2...
Is it 0.62 gram