What is the electron configuration of Iron

What is the formula that this ionic compounds could form sr2+p3-o2-

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.

If 10.5 l of a at 0.98to 1.50 , is ?