Determination ofKsp of Ca(OH)2
Determination of Ksp of Ca(OH)2
(Add Ca(OH)2 into different concentration of NaOH solutions,then react with HCl)
1. What is the expression of Ksp of Ca(OH)2?
2. Explain the variation in concentration of Ca2+ as the concentration of OH- increases.
3. Explain whether the following reaction is redox.
Ca(OH)2=Ca2+ + 2OH-
Is it possible to determineEred?
4 Is it possible to use higher concentration of NaOH? WHY?
5. Whether HCl of H2SO4 is suitable to replace NaOH in preparation of stock solutions? WHY?
- 1 十年前最愛解答
1. Ca(OH)2(s)<-->Ca2+(aq) + 2OH-(aq)
Ksp of Ca(OH)2 = [Ca2+][OH-]^2
as Ca(OH)2 is a solid, its conc. is const.
2. if addition of [OH-] is increased, eqm will shift to the left
as a result, less Ca(OH)2 will dissolve
3. this reaction is not a redox since there is no changes in oxidation states of any chemical species
as no redox reaction is existed, we cannot determine Ered
4. [NaOH] should not be too high
once [OH-] is too high, precipitation will occur instead of dissolution of Ca(OH)2
5. wt stock solution?
u mean preparing standard Ca(OH)2??
if yes, then neither HCl nor H2SO4 are not suitable for preparing standard Ca(OH)2
moreover, HCl and H2SO4 will undergo neutralization with Ca(OH)2 rather than standardization
hope this can help u資料來源： me