Couple of problems left over from Chem homework I didn't get.

AI Thread Summary
The discussion revolves around two chemistry problems involving titration calculations. The first problem requires determining the molecular weight of an acid using a titration with NaOH, where 1.863 grams of the acid is titrated with 70.11 mL of 0.1302 M NaOH. The second problem involves finding the concentration of Fe(II) after titrating a 10.00 mL aliquot with 21.35 mL of 0.3136 M Ce(IV). The user attempted to calculate moles of NaOH and Ce(IV) but expressed confusion over their methods and results. The key focus is on applying the mole ratio and titration formulas correctly to solve these problems.
Radja24
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Hi, I'm taking AP Chem this year, and we just had this big assignment. I got through most of it, but here's some I need a walkthrough with.

Homework Statement


A titration is done using .1302M NaOH to determine the molecular weight of an acid. The acid contains one acidic hydrogen per molecule. If 1.863 grams of the acid requires 70.11mL of the NaOH solution, what is the molecular weight of the acid?

Here's the second one:

Fe (II) + Ce (IV) -----> Fe (III) + Ce (III)

What is the concentration of Fe(II) if it requires 21.35mL of .3136 M Ce (IV) to titrate a 10.00mL aliquot to the endpoint?

Attempt:

1st one, I tried to get moles of NaOH and then multiply it by 110 to get 1 mole, then multiply 1.863 by 110...but that makes no sense.
For the second, I tried using MfVf formula for titration, and before that I tried to get the moles of Ce (Iv) once again, and then find the limiting agent and plug and go from there, but I sincerely am stuck.
These were two ones I couldn't get really get after some nonsense work. Please help...
 
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The basic plan for both is answer the question of how many MOLES were titrated?
Each of those analyses use 1:1 mole ratios of titrant to analyte being sought.

(moles per liter of titrant)*(liters of titrant) = moles of titrant
 
For the second one I did .3136 * .02135 to get .0067 moles Ce (IV)m then multiplied .0067 * .01 Liters to get .000067 moles of titrant, and then I divided that number by .01 L to get .0067 M as my answer
 
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