Suppose 1.624g of salt FeSO4 is placed in a 250mL flask to which 50mL of water and 10 mL of 3M H2SO4 are added. How many mL of .1062 M KMnO4 solution are required to reach the endpoint?
To find out how many mL of 0.1062 M KMnO4 solution is needed to reach the endpoint, we need to perform a titration calculation. Here's how you can proceed:
1. Start by calculating the moles of FeSO4 present in 1.624 g using its molar mass. The molar mass of FeSO4 is (55.845 g/mol) + (32.065 g/mol + 4 * 16.00 g/mol) = 151.909 g/mol. Therefore, the moles of FeSO4 are calculated as follows:
moles of FeSO4 = (mass of FeSO4) / (molar mass of FeSO4)
= 1.624 g / 151.909 g/mol
2. Next, calculate the moles of H2SO4 present in the 10 mL of 3M solution. The molarity (M) of a solution is defined as moles of solute per liter of solution. Therefore, the moles of H2SO4 can be calculated as follows:
moles of H2SO4 = (volume of H2SO4 solution) * (molarity of H2SO4)
= 10 mL * 0.003 M
3. Determine the limiting reagent by comparing the moles of FeSO4 to the moles of H2SO4. The reactant that produces the least amount of product is the limiting reagent. In this case, the limiting reagent will be the one that corresponds to the smaller number of moles.
4. Use the stoichiometry of the balanced equation to find the moles of KMnO4 required to react with the limiting reagent. The balanced equation for the reaction between FeSO4 and KMnO4 is:
5FeSO4 + 2KMnO4 + 8H2SO4 → 5Fe2(SO4)3 + 2MnSO4 + K2SO4 + 8H2O
From the balanced equation, you can see that 2 moles of KMnO4 react with 5 moles of FeSO4. Therefore, the moles of KMnO4 required can be calculated as follows:
moles of KMnO4 required = (moles of FeSO4) * (2 moles of KMnO4 / 5 moles of FeSO4)
5. Finally, calculate the volume of 0.1062 M KMnO4 solution required to reach the endpoint using the molarity and the moles of KMnO4 required:
volume of KMnO4 solution = (moles of KMnO4 required) / (molarity of KMnO4 solution)
Remember to always check your units as you perform the calculations to ensure they are consistent.