InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
An acid-base indicator which is a weak acid has a `pK_(a)` value `=5.5`. At what concentration ratio of sodium acetate to acetic acid would the indicator show a colour half-way between those of its acid and conjugate base forms?A. `4.93 : 1`B. `6.3 : 1`C. `5.62 : 1`D. `2.37 : 1` |
|
Answer» Correct Answer - C At Half way `[HIn]=In` `pH=5.5+(["salt"])/([acid])5.5` `=pK_(a)+log``(["salt"])/([acid])` `log``(["salt"])/([acid])=0.75implies (["salt"])/([acid])=5.62` |
|