Homework Help: Chemistry Problem

Posted by Amy on Tuesday, January 22, 2013 at 3:04pm.

A student proposes to use visible spectroscopy to measure the kinetics of the permanganate/oxalic acid reaction. The initial permanganate solution was very dark. For a 1 cm sample cell, the absorbance A = 2,500[MnO4]. As a practical rule of thumb, Beer's law is only accurate below an absorbance value of A = 1.00. This limits the initial permanganate concentration that can be used.

A: What is the maximum permanganate concentration that can be used and still have A = 1.00?

B: If the detection limit for the spectrometer is A = 0.01, what is the minimum permanganate concentration that can be detected?

C: The rate law for the reaction was determined to be:

[MnO4-]0/t = 0.052[mnO4]0^-1.29 * [H2C2O4]0^0.76

If [H2C2O4]0 = 0.30 mol/L and [MnO4] is the maximum it can be for visible spectroscopy, how long would it take for the the permanganate to be used up? Remember the rate law given above was for the average rate for the complete conversion of MnO4- to Mn2+.

Chemistry Problem - DrBob222, Tuesday, January 22, 2013 at 6:47pm
A. If A = 2,500(MnO4^-) and you want A to be 1.00, Substitute 1.00 into the above and solve for (MnO4^-).

B. Substitute 0.01 for A and solve for (MnO4^-)

I don't get c.

Answer this Question

Related Questions

Chemistry - What is the mole of oxalic acid? Equation:H2C2O4 + 2NaOH---> ...
college Chemistry - What is the mole of oxalic acid? Equation:H2C2O4 + 2NaOH---&...
chem lab - In a pottasium permanganate and oxalic acid titration..why do we add ...
chemistry - prepare M/20 solution of oxalic acid. Find out the molarity and ...
chemistry - The reaction of MnO4- with oxalic acid (H2C2O4) in aciic solutiob, ...
chem - sorry . Can you please help me with this questions If you know? Oxalic ...
Chemistry - A student did not fully mix the solution of Oxalic Acid in the ...
Chemistry - You have a solution that contains 5.0 grams of oxalic acid dissolved...
Chemistry - The amount of oxalic acid in a sample was determined by the reaction...
Chemistry - You have a solution that contains 5.0 grams of oxalic acid dissolved...

For Further Reading

First Name:
School Subject:
Answer: