In: Chemistry
3A. Using Table 11-3, Common Indicators, predict the color of Thymol Blue (note that there are 2 transition ranges for this indicator) at the following solution pH’s:
pH = 1.00 color__________
pH = 3.00 color__________
pH = 7.50 color __________
pH = 10.00 color
3B. Define the term “indicator error”:
3C: Explain why the first derivative of the titration curve can be used to identify the equivalence point of an acid-base titration (or equivalence p
3D: Explain the effect of pKa on endpoint detection for the titration of a weak acid with a strong base:oints for polyprotic acids).
3E: Explain the effect of acid strength (molarity) on endpoint detecton for the titration of a weak acid with a strong base.
3B:
pH:1.00 color intense red,
pH:3.00 color yellow,
pH:7.50 color yellow,
pH:10.00 color intense blue.
3B. Indicator error is called to a slight difference between the change in indicator color and the actual equivalence point of the titration.
3C. The equivalence point can be determine using the first derivate because in it the slope of the straight line (titration curve) indicate the equivalence point. Also you can graph the first derivade (dpH/dV) Vs.Volume. where the greatest peak is the volume where the equivalence point occurs.
3D. It moreless shows us, the pH when the each inflection point will be occurs, and also it can be help us to select an indicator to use (different ranges). The endponit is when the acid give the last proton (less acidic than previous ones). It means, that is needed less volume to reach it.
3E. The molarity strength for an acid affect in how many volume of strong base must be use, due to the moles that have to neutralize is bigger. It doesn't mean that the pH where the endpoint is reached will be increase.