Nitrogen is a vital component of proteins and nucleic acids, and thus is necessary for life. The atmosphere is composed of roughly 80% N2, but most organisms cannot directly utilize N₂for biosynthesis. Bacteria capable of €œfixing€ nitrogen (i.e., converting N₂to a chemical form [such as NH₃] which can be utilized in the biosynthesis of proteins and nucleic acids) are called diazotrophs. The ability of some plants like legumes to fix nitrogen is due to a symbiotic relationship between the plant and nitrogen-fixing bacteria that live in the plant€™s roots. Assume that the hypothetical reaction for fixing nitrogen biologically is 

a. Calculate the standard enthalpy change for the biosynthetic fixation of nitrogen at T = 298 K. For NH₃(aq), ammonia dissolved in aqueous solution, ˆ†H^o_f = €“ 80.3 kJ mol^-1

b. In some bacteria, glycine is produced from ammonia by the reaction

Calculate the standard enthalpy change for the synthesis of glycine from ammonia. For glycine, , ˆ†H^o_f = €“ 537.2 kJ mol^-1. Assume T = 298 K.

c. Calculate the standard enthalpy change for the synthesis of glycine from nitrogen, oxygen, and methane.

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N,(g) + 3H,O() → 2NH;(ag) + 0,(g) NH3 (ag) + 2CH4(g) +0,(8) — NH,сH,COоң) + зн,0(0) NH,CH,COOHS) + зH,00)