Question
A solution of 25mL of 0.5M c2h5nh2 is titrated with hydrochloric acid solution. During titration 5mL of .5M hcl is added dropwise. As volumes are additive. Calculate the pH of the resulting solution
Answers
DrBob222
millimols C2H5NH2 = mL x M = 25 x 0.5 = 12.5
mmols HCl = 5 mL x 0.5M = 2.5 HCl.
.......C2H5NH2 + HCl --> C2H5NH3^+ + Cl^-
I.......12.5.......0.........0......0
added............2.5................
C.......-2.5....-2.5........+2.5....2.5
E.......10.0......0..........2.5....2.5
This is a buffered solution. Use the Hendersen-Hasselbalch equation.
base = 10 mmols.
acid = 2.5 mmols
mmols HCl = 5 mL x 0.5M = 2.5 HCl.
.......C2H5NH2 + HCl --> C2H5NH3^+ + Cl^-
I.......12.5.......0.........0......0
added............2.5................
C.......-2.5....-2.5........+2.5....2.5
E.......10.0......0..........2.5....2.5
This is a buffered solution. Use the Hendersen-Hasselbalch equation.
base = 10 mmols.
acid = 2.5 mmols