Question

Nitrogen is a vital element for all living systems, but except for a few types of bacteria, blue-green algae, and some soil fungi, most organisms cannot utilize N2 from the atmosphere. The formation of "fixed" nitrogen is therefore necessary to sustain life, and the simplest form of fixed nitrogen is ammonia NH3. A possible pathway for ammonia synthesis by a living system is:

12N2(g)+32H2O(l)→NH3(aq)+32O2(g)

where (aq) means the ammonia is dissolved in water.

Substance	ΔG∘f (kJ⋅mol−1)
N2(g)	0
H2O(l)	−237.1
NH3(aq)	−26.5
O2(g)	0

Calculate ΔG∘f for the biological synthesis of ammonia at 298 K.

Calculate the equilibrium constant for the biological synthesis of ammonia.

Answer 1

1/2N2(g)+3/2H2O(l)→NH3(aq)+3/2O2(g)

ΔG∘rxn   = ΔG∘f products - ΔG∘f reactants

                 = 3/2*0 -26.5-(1/2*0 + 3/2*-237.1)

                 = -26.5+355.65

                  = 329.15KJ/mole    = 329150J/mole

ΔG∘    = -RTlnK

329150 = -8.314*298*2.303logK

329150     = -5705.84logK

logK          = -329150/5705.84

logK         = -57.68

K            = 10^-57.68    = 2.1*10^-58>>>>>answer