Lab Experiment 8 Equilibrium II – Le Chatelier’s Principle Part D Weak AcidBase
ID: 552432 • Letter: L
Question
Lab Experiment 8 Equilibrium II – Le Chatelier’s Principle Part D Weak AcidBase Indicator Equilibrium Given: HInBTB H+ + InBTB 2. Describe the different colors observed for this system under acidic and basic conditions and identify which color corresponds to HInBTB and which color to InBTB . 3. In step b (b. Add NaOH dropwise until a single drop makes the solution green. Swirl/stir to mix thoroughly after adding each drop. Record observations as well as the drop count and the concentration of NaOH used. If you go past green, add another drop of HCl and try again. Note – there are two different concentrations of NaOH available at the station to help (0.1M and 0.01M);some drops of both may be necessary to get the green color) , NaOH is added until the solution turns green. Describe the relative amounts of HInBTB and InBTB that are present when the solution is green and explain why NaOH is able to cause this color change.
Explanation / Answer
HInBTB H+ + InBTB
2) BTB has three colours according to pH range 6.0-7.6
3) When solution is green, it is in pH range around neutral. So [HInBTB] = [InBTB]
NaOH causes this colour change because initially at lower pH solution is yellow, so NaOH shifts pH to neutral
and turns solution green.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.