a is solved using the Hendrson-Hasselbalch equation.
b. Add 0.125 to pH from a. I think that will be about 4.925 but you need to confirm that. Then find mmoles acetic acid and mmoles acetate that you have at the beginning of problem b, divide by mL to find M of each, and multiply by 500 mL to find mmoles of each in 0.5 L.
Adding KOH will mean (acetate) = mmoles+x and (acetic acid) will be mmoles-x. Plug that into the Henderson-Hasselbalch equation and solve for x. Then convert that to grams KOH for the 0.5 L buffer solution. Post your work if you get stuck.
A buffer is prepared by mixing 205 mL of .452 M HCl and .500 L of .400 M sodium acetate. (Ka =1.80 x 10^-5)
a) What is the pH?
b) How many grams of KOH must be added to .500 L of the buffer to change the pH by .125 units?
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I set up the Hendrson-hasselbalch equation and i got 4.95=log((.4-x)/(1.1+x) but now i'm stuck on how to figure out x
1 answer