Pre-Lab Questions:
1. Why are some insoluble salts said to be in a state of equilibrium and thus given a K value?
Insoluble salts, by definition, have extremely low solubility in water. So when they are said
to be in equilibrium, it means they have achieved the maximum degree of dissolution
possible for that salt given its inherent low solubility.
2. Calculate the Gibbs Free Energy for the following reaction at 25°C if the enthalpy value ( ΔH) is
177.8 kJ and entropy value ( ΔS) is 160.5 J. Is the reaction spontaneous at this temperature? Why or
why not? CaCO3 (s) CaO (s) + CO2 (g)
3. Complete the following phase: If K is numerically greater than
1, then lnK=positive, and the reaction is spontaneous going in the forward direction.
4. Give two examples of processes that increase entropy.
Spreading of heat energy: When heat flows from a hot object to a cold object, entropy
increases. Like heat flowing from a hot cup of coffee to the surrounding air and table in a
room
1. Why are some insoluble salts said to be in a state of equilibrium and thus given a K value?
Insoluble salts, by definition, have extremely low solubility in water. So when they are said
to be in equilibrium, it means they have achieved the maximum degree of dissolution
possible for that salt given its inherent low solubility.
2. Calculate the Gibbs Free Energy for the following reaction at 25°C if the enthalpy value ( ΔH) is
177.8 kJ and entropy value ( ΔS) is 160.5 J. Is the reaction spontaneous at this temperature? Why or
why not? CaCO3 (s) CaO (s) + CO2 (g)
3. Complete the following phase: If K is numerically greater than
1, then lnK=positive, and the reaction is spontaneous going in the forward direction.
4. Give two examples of processes that increase entropy.
Spreading of heat energy: When heat flows from a hot object to a cold object, entropy
increases. Like heat flowing from a hot cup of coffee to the surrounding air and table in a
room
