The reaction for the decomposition of ammonia is : 

2 NH3 (g) ⇌ N2(g) + 3 H2 (g) 

At equilibrium, the concentration of ammonia is 2.25 mol/L, nitrogen is 1.5 mol/L and hydrogen is 3.5 mol/L, at a certain temperature. Under the same conditions, a reaction vessel contains 0.75 mol/L of ammonia, 1.5 mol/L of nitrogen, and 3.3 mol/L of hydrogen. 

a. Is the system at equilibrium?

b. which reaction is favored. 

c. which concentration(s) is are increasing