Question

11- The pH of a sodium acetate-acetic acid buffer is 4.70. Calculate the ratio [CH3COO−] / [CH3COOH].






1- Calculate the pH of a 0.20 M NH3/0.20 M NH4Cl buffer after the addition of 25.0 mL of 0.10 M HCl to 65.0 mL of the buffer.


A- Enter your answer in the provided box.

A 21.0−mL solution of 0.110 M CH3COOH is titrated with a 0.240 M KOH solution. Calculate the pH after the following additions of the KOH solution:

(a) 0.00 mL
=_____


(b) 5.00 mL
=_______


C- Enter your answer in the provided box.

In a titration experiment, 21.9 mL of 0.813 M HCOOH neutralizes 24.4 mL of Ba(OH)2. What is the concentration of the Ba(OH)2 solution?
_____M

D- a) Calculate the pH of the 0.39 M NH3/ 0.73 M NH4Cl buffer system.

pH =


(b) What is the pH after the addition of 20.0 mL of 0.075 M NaOH to 80.0 mL of the buffer solution?

pH =



E- What mole ratio would you need to prepare a liter of "carbonate buffer" at a pH of 9.96?


______: 1.0 : 0

A) NaHCO3 : H2CO3 : Na2CO3
B) Na2CO3 : NaHCO3 : H2CO3

Choose the order of the compounds that is represented in the numeric ratio.



F- Enter your answer in the provided box.

The pH of a bicarbonate-carbonic acid buffer is 6.18. Calculate the ratio of the concentration of carbonic acid (H2CO3) to that of the bicarbonate ion (HCO3−).
(Ka1 of carbonic acid is 4.2 × 10−7.)

[H2CO3]
[HCO3−]
=