Question

What volume of 0.200M of aqueous solution of formic acid, a weak monoprotic acid (KA =
1.78x10-4) and 0.200M aqueous solution of NaOH would you mix to prepare a 500mL of a
buffer solution of pH = 4.0.

I know I need to use the H-H equation, I'm just not sure what I plug in and where. I am also not sure if I need to use an ICE chart or not.

4.0 =( 1.78x10^-4) + log ([HCOO-]/0.2)

with the 0.2 coming from the concentration of formic acid.

I am also unsure of if I need to use the MaVa=MbVb equation...

Any guidance on this question would be very helpful.

Answer 1

Thank you for answering this below Dr Bob

Answer 2

I responded at your post below. In fact I probably did more than you needed but take a look.