Substitute the concentrations into the equilibrium constant equation Ka-HIACVHAc H]=Ka×[ HACAC] =1.70×10-5×0.10/0.10 =1.70×105(mol.L) pH=477
Substitute the concentrations into the equilibriumconstant equation Ka = [H+ ][Ac- ]/[HAc] [H+ ] = Ka [HAc]/[Ac- ] = 1.70 10-5 0.10/ 0.10 = 1.70 10-5 (mol.L-1 ) pH = 4.77
Step 3. Calculate solution's pH value when add hydrochloric acid HAC H++ AC Starting 0.10 0.10 Change +0.01 -0.01 Equilibrium 0.10+0.01 0.10-0.01 Step 4. Substitute the equilibrium concentration into the equilibrium-constant equation H+]=Ka×[ HACVAC] =1.70×10-5×0.11/0.09 =2.07×103 H=4.68 ApH=..68-0.09(pH unit)
Step 3. Calculate solution’s pH value when add hydrochloric acid HAc H+ + AcStarting 0.10 0.10 Change +0.01 -0.01 Equilibrium 0.10+0.01 0.10-0.01 Step 4. Substitute the equilibrium concentration into the equilibrium-constant equation [H+ ] = Ka [HAc]/[Ac- ] = 1.70 10-5 0.11/ 0.09 = 2.07 10-5 pH = 4.68 pH = 4.77–4.68= 0.09 (pH unit)
Definition of buffer solution A buffer solution is a solution characterized by the ability to resist changes in pH when limited amounts of strong acid or strong base are added to it
Definition of buffer solution : A buffer solution is a solution characterized by the ability to resist changes in pH when limited amounts of strong acid or strong base are added to it
2. Composition of Buffer Solution Buffer solution consist of weak acid and its conjugate base or weak base and its conjugate acid. The conjugate acid-base pair are called buffer system or buffer pair Important bufter pair such as HAC --AC NH4---- NH3 H2CO3-HCO3 HaPOA---- HPO H2PO4 --HPO4 HPO42-----POA3
2. Composition of Buffer Solution Buffer solution consist of weak acid and its conjugate base or weak base and its conjugate acid. The conjugate acid-base pair are called buffer system or buffer pair. Important buffer pair such as: HAc ---- AcNH4 + ---- NH3 H2CO3 ---- HCO3 - H3PO4 ---- H2PO4 - H2PO4 - ---- HPO4 2- HPO4 2- ---- PO4 3-