Practice the data manipulation you will need to carry out to calculate the Ka value of a weak acid from titrimetric data:
a. If 20.00 mL of 0.10 M NaOH solution were required to reach the equivalence point, how many moles of weak, monoprotic acid (HA) were present in the solution being titrated?
0.02L*(0.10mol/L) =0.0020 mol of HA
b. What volume of NaOH solution would have been required to reach the half-equivalence point?
20.00mL/2 =10.0mL
c. How many moles of acid (HA) were present in solution at the half-equivalence point? How many moles of its conjugate base (A-) present at the half-equivalence point?
d. If the pH at the half-equivalence point was 3.74, what is the pKa of acid HA? From this, what is its Ka value? From the Ka value, what is the identity of acid HA?
I know c and d are required to use the henderson-hasselbalch equation pH= pKa + log (n conjugate/ n weak acid) but I'm a bit confused... can someone please help??
a. If 20.00 mL of 0.10 M NaOH solution were required to reach the equivalence point, how many moles of weak, monoprotic acid (HA) were present in the solution being titrated?
0.02L*(0.10mol/L) =0.0020 mol of HA
b. What volume of NaOH solution would have been required to reach the half-equivalence point?
20.00mL/2 =10.0mL
c. How many moles of acid (HA) were present in solution at the half-equivalence point? How many moles of its conjugate base (A-) present at the half-equivalence point?
d. If the pH at the half-equivalence point was 3.74, what is the pKa of acid HA? From this, what is its Ka value? From the Ka value, what is the identity of acid HA?
I know c and d are required to use the henderson-hasselbalch equation pH= pKa + log (n conjugate/ n weak acid) but I'm a bit confused... can someone please help??