Ca(OH)2 (s) precipitates when a 1.0 g sample of CaC2(s) is added to 1.0 L of distilled water at room temperature. If a 0.064 g s
ample of CaC2 (s) (molar mass 64 g/mol) is used instead and all of it reacts, which of the following will occur and why? (the value of Ksp for Ca(OH)2 is 8.0 x 10-8)(A) Ca(OH)2 will precipitate because Q >K sp.(B) Ca(OH)2will precipitate because Q K sp.(D) Ca(OH)2 will not precipitate because Q
Ksp for Ca(OH)2 has already been stated in the question as 8.0 x 10-8mol2dm-6
The value of the reaction quotient depends heavily on the concentration of the reactants. As the initial concentration of the calcium carbide decreases considerably, the reaction quotient decreases until Q<Ksp hence the Ca(OH)2 will not precipitate from solution.
Here the factor that Elle is controlling is the temperature. So temperature here is the independent variable and the dependent variable is the rate of evaporation of water. Independent variable is controlled during the experiment setup and the outcome of the dependent variable depends on the independent variable.
