Editing Lab Test Acid Base Titration And Buffer

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1. Please describe the steps and apparatus to titrate a weak acid with a standard strong base (i.e. known Molarity of base). Assume that you are looking for the molar mass of the acid. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2. Give the mass of the unknown monoprotic weak acid and concentration of the standard strong base (assume one OH1- per base molecule), describe the math steps to determine the molar mass of the acid. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3. I did the experiment from Question using a weak monoprotic acid, HX and titrated it with the standard strong base, <nowiki>NaOH</nowiki>. The equivalence point is reached when 25.0ml of <nowiki>NaOH</nowiki> has been added.

a.In graph below, sketch the titration curve, showing the pH changes that occur as the volume of <nowiki>NaOH</nowiki> solution added increases from 0 to 35.0ml. Clearly label the equivalence point on the curve.

b. Describe how the value of the acid-dissociation constant, Ka, for the weak acid acid HX could be determined from the graph below.

c. Which of the following pH indicator would you use for the titration on the graph below and Why? 
Methyl red Ka = 1E-5 
Cresol red Ka = 1E-8 
Alizarin yellow Ka = 1E-11 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4. On the graph below, draw the titration curve of a weak base being titrated by a standard monprotic strong acid, HCl. Then circle the three main areas of the titration and label A, B and C. Then draw a picture/bucket for each area and write the main species in that bucket. Under each picture, write the chemical equation and mathematical manipulation for each bucket to determine the pH. (Hint, the answer pH = -log [H+] is not always the correct answer). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5. What are the two ways you can create an acid buffer? 
 
Consider the titration of 40.0ml of 0.100M <nowiki>NH</nowiki>3. Calculate the pH of the solution upon addition of the 25.0ml of 0.100M <nowiki>HCl</nowiki>. 
Kb,NH3 = 1.8E-5

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