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CH3041
THE MAIN ‘N’
CHEMICALS
N is found in a variety of oxidation
states:
NO3-,
HNO3 (V); NO2 (IV); NO2- (III);
NO (II); N2O (I); NH3, NH4+ (-III)
NO (II); N2O (I); NH3, NH4+ (-III)
Atmosphere -
N2 (NO2, NO, N2O)
• Lightning N2 + O2 ® 2NO + O2 ®
(& Cars) 2NO2 + H2O ® HNO2 + HNO3
(& Cars) 2NO2 + H2O ® HNO2 + HNO3
• high temperatures eg. lightning 4000K
Terrestrial
- NH4+, NO3-
• Nitrogen fixation N2 + 8H+ + 6e- ® 2NH4+
DG -120 kJ/mol ‘CH2O’+ H2O ® CO2+ 4H+ + 4e-
3{‘CH2O’}+ 3H2O + 2N2 + 4H+ ® 3CO2+ 4NH4+
- this links the C cycle to the N cycle.
- this links the C cycle to the N cycle.
