64.9 g of iron(II) sulfate heptahydrate, a supplement to treat anemia, is heated in an oven until all the water is driven off. What is the mass of the anhydrous compound?

Amixture initially contains a, b, and c in the following concentrations: [a] = 0.300 m , [b] = 1.05 m , and [c] = 0.550 m . the following reaction occurs and equilibrium is established: a+2b⇌c at equilibrium, [a] = 0.140 m and [c] = 0.710 m . calculate the value of the equilibrium constant, kc.