0330prelabanswersExperiment5Fall2011 - PRE-LABORATORY...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
PRE-LABORATORY QUESTIONS EXPERIMENT 5 1. A student is asked to prepare 200. mL of a 0.10 M buffer with pH = 8.30. There are two weak acids the student can choose from. Acid A has a pK a of 10.50 and Acid B has a pK a of 7.50. Which acid should the student pick? Briefly explain your choice. pH ranges: 11.50-9.50 for Acid A 8.50-6.50 for Acid B The best choice would be Acid B since the desired pH is in the range based on the pK a . 2. How many grams of the conjugate base of molar mass 175 g/mol will have to be added to a solution of a weak acid to make 200. mL of a buffer in which the concentrations of the weak acid and its conjugate base are each 0.200 M? (0.200 mole/L) (0.200 L) = X g of the conjugate base/175 g/mole X = 7.00 grams of the conjugate base 3. Write the hydration reaction and the hydrolysis reaction for sodium nitrite, NaNO 2 . Will the pH of the solution be acidic, neutral or basic? Hydration:
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 2

0330prelabanswersExperiment5Fall2011 - PRE-LABORATORY...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online