Question

1.) a) Is the process of KNO₃ dissolving in water spontaneous at all temperatures studied? Is it spontaneous at higher or lower temperatures? Briefly explain.

b) Is the reaction in (a) one that gives off heat or requires heat? Briefly explain.

c) Is your value of ΔS consistent with the expected change in disorder for the reaction in Equation 1? Briefly explain.

2,) A few compounds exist whose solubility decreases as the temperature increases. How would the sign (positive, negative, no change) for ΔG, ΔH, and ΔS for these reactions be different from those values observed for the solubility if KNO₃? Briefly explain.

3.) a) What assumption is made about the reaction at the temperature at which crystals become visible?

b) If this assumption were not true, would the value of K_sp differ? If so, will it be lower or higher?

c) How about the value for ΔG? Will ΔG be higher or lower?

4.) Explain what will happen to the K_sp if not all the salt dissolves in the solution preparation? Do you expect your result to increase or decrease because not all of the salt dissolves?

5.) a) What does the sign of the ΔG tell you about the dissolution process for this experiment?

b) Is the dissolution process spontaneous at all temperatures? If not, at what temperature does spontaneity change?

Answer 1

1.) a) Is the process of KNO3 dissolving in water spontaneous at all temperatures studied? Is it spontaneous at higher or lower temperatures? Briefly explain. yes, KNO3 dissolutino is spontaneous at any T, due to dH dS values . it favours high T as wlel

b) Is the reaction in (a) one that gives off heat or requires heat? Briefly explain.KNO3 dissolution is endohtermic, meaning it absorbs heat

c) Is your value of ΔS consistent with the expected change in disorder for the reaction in Equation 1? Briefly explain. yes, it is, menaing that dS dissolution is posisitve, favoured by T