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NamikazeBurst
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Homework Statement
How to find concentration of NaOH to titrate ASA with 30-40 mL
I am doing a lab in which I need to use a base with a known concentration (a standard solution that I have to dilute to make a secondary standard) to react with an acid with an unknown concentration. I then have to find the mass of the acid.
I am wondering how I am supposed to find what concentration my secondary standard is supposed to be. I need to use 30-40 mL of it per tablet of ASA (the acid we are using), which are 325 mg each. I guessed 0.1 mol/liter, which can be used, but doesn't follow under 30-40 mL. How do I determine the concentration of secondary standard that will give me 30-40 mL of NaOH (the base) which will dilute 325 mg of ASA dissolved in 10 mL of ethanol?
Summary:
- I have to make a standard solution and dilute to make a secondary standard
- I must use NaOH (starting as a solid) as the base
- I must use 325mg of acetylsalicylic acid as the acid with the unknown concentration
- For best results, I should use 30-40 mL of the secondary standard to perform the titration
- The ASA is dissolved in 10 mL of ethanol
- I am trying to figure out the concentration of the secondary standard of NaOH that will titrate with 30-40 mL
I tried using 0.1 mol/L of NaOH as it seemed dilute enough but not too dilute. I got values of 4g of initial NaOH. My teacher said to work backwards from the equation (ASA + NaOH -> H20 + NaASA-H) [If this is correct, I didn't type the actual chemical equation], but I do not know how that will help. He has not taught us how to calculate equivalence points.
Homework Equations
C = n/v
n = m/M
CiVi = CfVf
The Attempt at a Solution
4g of NaOH diluted to 250 mL after making a primary standard
0.1 mol/liter --> teacher says it will work but is not optimal