3. Determine if the following system is at equilibrium. If not, in which direction will the system need to shift to reach equilibrium? SO2Cl2(g) ⇌ SO2(g)+Cl2(g) [SO2Cl2] = 0.12 M, [Cl2] = 0.16 M and [SO2] = 0.050 M. Kc for the reaction is 0.078.

The system need to shift to the right

Explanation:

For the reaction:

SO2Cl2(g) ⇌ SO2(g)+Cl2(g)

Reaction quotient, Q, is:

Q = [SO2] [Cl2] / [SO2Cl2]

If Q = Kc, the system is in equilibrium, if Q > Kc, the system need to shift to the left, if Q < Kc,  the system need to shift to the right.

Replacing:

Q = 0.050 M×0.16 M / 0.12 M

Q = 0.067

As Kc = 0.078, Q < Kc, the system need to shift to the right.

I hope it helps!

1. for the first question, we must find the mass of the anhydrous salt, mgso₄. the molar mass for mgso₄·7h₂o is 246.47 g/mol, while that of mgso₄ is 120.37 g/mol.7.834 g mgso₄·7h₂o * 1 mol mgso₄·7h₂o/246.47 g * 1 mol mgso₄/1 mol mgso₄·7h₂o * 20.37 g mgso₄/mol = 0.647 g mgso₄

2. mass of water = mass of sample - mass of anhydrous salemass of water = 7.834 - 0.647 = 7.19 gpercent water in hydrate = 7.19/7.834 * 100 = 91.74%

your answer is a. the enthalpy of formation for a pure element in its standard state is always positive.