J.R. S. answered • 04/20/21
Ph.D. University Professor with 10+ years Tutoring Experience
1). If you already have standardized NaOH, then you would put that in the burette and use it to titrate the H2SO4. Using phenolphthalein, the color should go from redish-orange (in the H2SO4) to colorless when neutralization is reached. It will turn pink when the solution turns alkaline.
2). I don't think you want to titrate aspirin (acetylsalicylic acid) with H2SO4 because they are BOTH ACIDS.
Perhaps you want to use NaOH to titrate the aspirin. Please check your experimental design and come back with questions if you still have them. If using phenolphthalein, it would be red to orange in an acid solution, colorless in a neutral solution and pink in an alkaline solution.
J.R. S.
04/20/21
Henoch M.
thank you, this was very helpful04/20/21
Henoch M.
In my experimental design it says the following : Accurately weigh 3 or 4 tablets (or ca. 1.5 g of sample if supplied in powder form) into an Erlenmeyer flask, add accurately between 25 mL and 35 mL of the ca. 1 M NaOH solution (by burette) and 20 mL of distilled water to the flask. (Remember to write down the exact volume of ca. 1 M NaOH added.) 2. Simmer gently for 10 minutes to hydrolyse the acetyl salicylic acid. 3. After cooling the mixture, transfer it quantitatively to a 250 mL volumetric flask and dilute to the mark with distilled water. 4. Titrate in triplicate three 25.00 mL aliquots of this solution against the ca. 0.05 M H2SO4, after the addition of a few drops of phenol red to each flask.' what will be the color change in this case?04/20/21