[webassignbuddy]

I already know how to approach this problem.

1. ICE Table

             H-MOPS   +  OH^-    MOPS^- + H₂O
initial------(x)----------(x)--------(48)-------NA
change ---(-x)---------(-x)-------(+x)-------NA
final-------(~0)--------(~0)------(48+x)----NA

2. Since we wan to make a pH = 6.85 buffer:

pH = pKa + log(nb/na)
6.85 = (-log Ka) + log(___ /___)
6.85 = 7.19 + log(___ /___)
-0.34 = log(___ /___)
10^(-0.34) = log(___ /___)
0.457 = (___ /___)

Solve for x (which will be in mmol)

3. x mmol x (0.31 ml/mmol of H-MOPS) = Answer

The problem is my table ISN'T set up right!
They gave me Mm of H-MOPS but I don't know what to use it for...
I need help setting up this table properly

[webassignbuddy]

The answer is supposed to be 346.6 mL

[webassignbuddy]

Oh wait nevermind. I got the answer!