Calcium Carbonate Decomposes at High Temperatures to Give Calcium Oxide $\circ$

Calcium carbonate decomposes at high temperatures to give calcium oxide and carbon dioxide as shown below.CaCO₃(s) ⇌ CaO(s) + CO₂(g) The K_P for this reaction is 1.16 at 800 ^$\circ$ C. A 5.00 L vessel containing 10.0 g of CaCO₃(s) was evacuated to remove the air, sealed, and then heated to 800 ^$\circ$ C. Ignoring the volume occupied by the solid, what will be the mass of the solid in the vessel once equilibrium is reached

A) 6.9 g of solid
B) 7.1 g of solid
C) 7.3 g of solid
D) 7.5 g of solid
E) None of the above