BCHM 210 Midterm: Nitrogen Fixation
Document Summary
Nitrogen fixation: conversion of atmospheric nitrogen to ammonia to provide nitrogen for the synthesis of amino acids and other metabolites. In biological systems n2 is reduced and hydrogen is simultaneously produced: the reaction is thermodynamically favored, but kinetically very slow because of high. N2 + 8e- + 8h+ energy (instability) of some transition state complexes along the reaction pathway: biological n2 fixation takes place only in some microorganisms (diazotrophic bacteria). In most cases, 2 atps are hydrolyzed for each electron transferred, so the reaction becomes: n2 + 8e- + 8h+ + 16atp + 16h2o 2nh3 + h2 + 16adp + 16pi. Nitrogen (n2) goes to 8 electron and 8 protons this produces two nh3 and one h2. We need to be able to balance this equation. In order to break the bond between n-n, it takes 225 kcal; a carbon-carbon takes 83 kcal, and oxygen-oxygen bond takes 35 kcal; hence you need special apparatus to break.
