In lab, the ratio of moles C2O4^2-/Fe^3+ was 0.0063 to 0.0017, which is 3.7 . However, I am having a hard time deducing the formula and charge on complex ion. The unbalanced formula I had to use was:
Fe^3+(aq) + C2O4^2+(aq) = Fex(C2O4)y^(3x-2y)
Since the compound's name is Iron(III) salicylate, what is x and y?
I don't get the connection between the oxalate ion (C2O4^-2) and the name salicylate.
Sorry, forget the name of compound. How do I find x and y?
From your data I would do this but it's a stretch.
0.0063 = C2O4^-2
0.0017 = Fe^+3
Divide both by the smaller number which gives you 1 mole Fe to 3.7 moles C2O4^-2. Round the 3.7 to the nearest whole number (4.0) (that's the stretch) so that would make it Fe(C2O4)4 (x=1 and y = 4) so the charge on the ion you have is -5. I think the correct formula for the complex is
Fe(C2O4)3^-3
Is it supposed to be Fe(C2O4)4^-5?
Why Fe(C2O4)3^-3?
You need to re-read my response. Your data shows it to be Fe(C2O4)4^-5 but the correct formula of the complex, I believe, is Fe(C2O4)3^-3.
To determine the values of x and y in the formula Fex(C2O4)y^(3x-2y) for the compound Iron(III) salicylate, you will need to use the given mole ratios and charge balances.
Here's how you can approach this problem step by step:
1. Identify the two ions present in the reaction: Fe^3+ and C2O4^2-.
2. Write down the balanced equation for the reaction based on the given unbalanced equation:
Fe^3+(aq) + 3.7 C2O4^2-(aq) = Fex(C2O4)y^(3x-2y)
Note: The coefficient 3.7 comes from the ratio of moles, which is given as 0.0063 to 0.0017. Rounding to one decimal place gives a ratio of 3.7.
3. Assign variables (x and y) for the unknown coefficients of the complex ion Fex(C2O4)y^(3x-2y).
4. Determine the total charge on each side of the equation. On the left side, the total charge is 3+ (from Fe^3+) + 2(-2) (from C2O4^2-) = -1. On the right side, the total charge is 3x (from Fe^3+) + y(-2) (from C2O4^2-).
Since both sides of the equation must have an equal total charge, you can equate these two expressions:
3+ - 4 = 3x - 2y - 1.
Simplifying the equation, you get:
-1 = 3x - 2y - 1.
5. Solve the equation for x and y:
-1 + 1 = 3x - 2y.
0 = 3x - 2y.
At this point, you have an equation with two variables (x and y), which means you need one more equation to solve for x and y.
6. Use the ratio of moles to form another equation:
0.0063 moles C2O4^2- / 0.0017 moles Fe^3+ = 3.7.
Dividing moles of C2O4^2- by moles of Fe^3+ gives:
(3.7) = [(0.0063 moles C2O4^2-)/(0.0017 moles Fe^3+)].
7. Rearrange the equation to isolate one variable:
(3.7) = [(0.0063 moles C2O4^2-)/(0.0017 moles Fe^3+)].
Multiply both sides of the equation by 0.0017 moles Fe^3+:
(3.7)(0.0017 moles Fe^3+) = 0.0063 moles C2O4^2-.
Simplifying, you get:
0.0063 moles C2O4^2- = (3.7)(0.0017 moles Fe^3+).
8. Use the molar ratios to form another equation:
0.0063 moles C2O4^2- = (3.7)(0.0017 moles Fe^3+).
Simplify the equation:
0.0063 = (3.7)(0.0017 moles Fe^3+).
Divide both sides of the equation by 0.0017 moles Fe^3+:
0.0063 / 0.0017 = 3.7.
Simplifying, you get:
3.7 = 3.7.
This equation verifies the ratio of moles, so it is correct.
9. Since the ratio of moles is valid, you can substitute the value of y into the equation obtained earlier to solve for x:
0 = 3x - 2y.
Substitute y = 3.7 into the equation:
0 = 3x - 2(3.7).
Simplify the equation:
0 = 3x - 7.4.
10. Solve the equation for x:
3x = 7.4.
x = 7.4 / 3.
x = 2.47.
Therefore, in the formula Fex(C2O4)y^(3x-2y) for the compound Iron(III) salicylate, x is approximately 2.47, and y is 3.7.