the following experiment was performed in the laboratory : an excess of solid SrCrO4 is vigorously shaken in water until a saturated solution is obtained. The excess solid is filtrated from the solution and 25.00 ml of the solution is titrated with 0.0115 M fe(no3)2 solution. A 30.60 ml portion of iron (ii) solution is needed to reach the endpoint. calculate the tsp of SrCro4. The titration reaction is CrO4^2- +3Fe^2+ +8H^+ ----> Cr^3+ +3Fe^3+ +4H2O
I have seen you write tsp twice. What in the world is tsp? Do you mean Ksp.
...........SrCrO4 --> Sr^2+ + CrO4^2-
I..........solid.......0........0
C..........solid.......x........x
E..........solid.......x........x
Ksp = (Sr^2+)(CrO4^2-)
You must determine the concentrations of Sr and CrO4. You do that with the Fe(NO3)2.
mols Fe(NO3)2 = M x L = ?
Using the titration equation, convert mols Fe(NO3)2 to mols CrO4^2-. That give you mols CrO4^2- in the 25.00 mL portion titrated. Convert that to mols in 1 L and that is (CrO4^2-). That is equal to (Sr^2+). Plug those into the Ksp expression and solve for Ksp.
Thanks!
To calculate the tsp (teaspoon) of SrCrO4, we need to determine the number of moles of SrCrO4 used in the experiment.
Here's how to calculate it:
1. First, let's calculate the number of moles of Fe(NO3)2 used in the titration.
Given: Volume of Fe(NO3)2 solution = 30.60 ml
Molarity of Fe(NO3)2 solution = 0.0115 M
Moles of Fe(NO3)2 = (volume in liters) × (molarity)
= 30.60 ml × (1 L / 1000 ml) × (0.0115 mol/L)
= 0.00351 mol
2. According to the stoichiometry of the reaction, 1 mole of SrCrO4 reacts with 3 moles of Fe(NO3)2.
Therefore, the number of moles of SrCrO4 is three times the number of moles of Fe(NO3)2 used in the titration.
Moles of SrCrO4 = 3 × (moles of Fe(NO3)2)
= 3 × 0.00351 mol
= 0.0105 mol
3. Finally, let's calculate the tsp (teaspoon) of SrCrO4.
To do this, we need to convert moles of SrCrO4 to grams using its molar mass and then convert grams to teaspoons (assuming we know the mass of 1 tsp SrCrO4).
You will need to determine the molar mass of SrCrO4 using the atomic masses of strontium (Sr), chromium (Cr), and oxygen (O) from the periodic table.
Let's assume the molar mass of SrCrO4 is M grams/mol.
Grams of SrCrO4 = Moles of SrCrO4 × M
= 0.0105 mol × M
Finally, convert grams of SrCrO4 to teaspoons using the known mass of 1 tsp SrCrO4.
Note: To complete the calculation, you will need to know the molar mass of SrCrO4 and the mass of 1 tsp of SrCrO4.