Question

Determine ΔSuniv for the following equation:

Ca2+ (aq) + SO42- (aq) → CaSO4 (s)

Answer 1

You can calculate delta S for the system and delta H for the system at 25 degrees C by using dHo formation and dSo formation and
dHo rxn = (n*dH products) - (n*dH reactants)
dSo rxn = (n*dH products) - (n*dH reactants).
What's the temperature.
dS surrounds = -dH/T
dS system from above
dSuniverse = dSsurroundings + dSsystem.